Uniform electric fields — Paper 1 · A Level Physics 9702

14 An electron is situated in a uniform electric field, as shown in the diagram. electron field What is the direction of the electric force acting on the electron? A downwards B to the left C to the right D upwards

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2004

30 In a uniform electric field, which statement is correct? A All charged particles experience the same force. B All charged particles move with the same velocity. C All electric field lines are directed towards positive charges. D All electric field lines are parallel.

1 marks

Answer: D

This question in 9702/11 Oct/Nov 2004

30 A positively charged particle is projected into a region of uniform electric field E. Which diagram represents the motion of the particle in the electric field? A B electric field in plane of the paper electric field in plane of the paper E E + + C D electric field into paper electric field into paper E E + +

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2005

31 Two large parallel plates X and Z are placed 5.0 mm apart and connected as shown to the terminals of a 200 volt d.c. supply. X Z P 200 V A small oil drop at P carries one excess electron. What is the magnitude of the electrostatic force acting on the oil drop due to the electric field between the plates? A 6.4 x 10–15 N B 6.4 x 10–18 N C 1.6 x 10–19 N D 4.0 x 10–24 N

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2005

29 Two parallel metal plates are at potentials of +800 V and +1300 V. Which diagram best shows the electric field between the metal plates? A B +800 V +1300 V +800 V +1300 V C D +800 V +1300 V +800 V +1300 V

1 marks

Answer: B

This question in 9702/11 May/June 2006

30 An electron of charge e is introduced between two metal plates a distance d apart. A potential difference V is applied to the plates as shown in the diagram. F d electron V Which expression gives the electric force F on the electron? eV V dV A B eVd C D d ed e

1 marks

Answer: A

This question in 9702/11 May/June 2006

30 An electric field exists in the space between two charged metal plates. + X Y – Which graph shows the variation of electric field strength E with distance d from X along the line XY? A B C D E E E E 00 00 00 00 d d d d

1 marks

Answer: C

This question in 9702/11 Oct/Nov 2006

29 An electron, travelling horizontally at constant speed in a vacuum, enters a vertical electric field between two charged parallel plates as shown. + + + + + electron electric field – – – – – What are the horizontal and vertical components of the motion of this electron when it is in the field? horizontal component of vertical component of motion motion A constant speed acceleration upwards B constant speed acceleration downwards C acceleration to the right acceleration downwards D acceleration to the right acceleration upwards

1 marks

Answer: A

This question in 9702/11 May/June 2007

30 The electric field strength between a pair of parallel plates is E. The separation of the plates is doubled and the potential difference between the plates is increased by a factor of four. What is the new electric field strength? A E B 2E C 4E D 8E

1 marks

Answer: B

This question in 9702/11 May/June 2007

16 A positive charge experiences a force F when placed at point X in a uniform electric field. The charge is then moved from point X to point Y. Distances r and s are shown on the diagram. Y r uniform electric field F X s What is the change in the potential energy of the charge? A decreases by Fs B increases by Fs C decreases by Fr D increases by Fr

1 marks

Answer: A

This question in 9702/11 May/June 2008

30 An electron enters the space between two parallel charged plates with an initial velocity u. + v e θ e u – While in the electric field, its direction changes by θ and it emerges with a velocity v. What is the relation between v and u? A v = u B v = u cosθ C v = u D v = u sinθ cos θ sin θ

1 marks

Answer: A

This question in 9702/11 May/June 2008

31 The diagram shows an oil droplet that has become charged by gaining five electrons. The droplet remains stationary between charged plates. +5000 V oil 0.8 cm droplet 0 V What is the magnitude and direction of the electrostatic force on the oil droplet? A 5.0 × 10–15 N upwards B 5.0 × 10–15 N downwards C 5.0 × 10–13 N upwards D 5.0 × 10–13 N downwards

1 marks

Answer: C

This question in 9702/11 May/June 2008

30 A particle has a charge of 4.8 × 10–19 C. The particle remains at rest between a pair of horizontal, parallel plates having a separation of 15 mm. The potential difference between the plates is 660 V. What is the weight of the particle? A 2.1 × 10−14 N B 2.1 × 10−15 N C 2.1 × 10−17 N D 1.1 × 10−23 N

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2008

27 The diagram shows the paths of two charged particles, X and Y, during their passage between a pair of oppositely charged metal plates, P and Q. P X Y Q The plates are charged such that the electric field between them is directed from Q to P. Which charges on X and Y will produce the observed paths? X Y A – – B – + C + – D + +

1 marks

Answer: A

This question in 9702/11 May/June 2009

28 There is a potential difference between a pair of parallel plates. Which values of potential difference and separation of the plates will produce an electric field strength of the greatest value? potential separation difference A 2V 2d d B 2V 2 V C 2 2d V d D 2 2 Space for working

1 marks

Answer: B

This question in 9702/11 May/June 2009

29 The diagram shows an electron, with charge e, mass m, and velocity v, entering a uniform electric field of strength E. electron v E x The direction of the field and the electron’s motion are both horizontal and to the right. Which expression gives the distance x through which the electron travels before it stops momentarily? mv mv mv 2 mv 2 A x = E B x = Ee C x = D x = 2 E 2 Ee

1 marks

Answer: D

This question in 9702/11 May/June 2009

28 The diagram shows two parallel horizontal metal plates held at a potential difference V. +V A small charged liquid drop, midway between the plates, is held in equilibrium by the combination of its weight and the electric force acting on it. The acceleration of free fall is g and the electric field strength is E. What is the ratio of the charge to mass of the drop, and the polarity of the charge on the drop? charge polarity mass g A positive E g B negative E E C positive g E D negative g Space for working

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2009

27 The diagram shows two parallel horizontal metal plates held at a potential difference V. +V A small charged liquid drop, midway between the plates, is held in equilibrium by the combination of its weight and the electric force acting on it. The acceleration of free fall is g and the electric field strength is E. What is the ratio of the charge to mass of the drop, and the polarity of the charge on the drop? charge polarity mass g A positive E g B negative E E C positive g E D negative g Space for working

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2009

26 Which row describes the circumstances under which forces act on a charged particle in a uniform electric field? charged particle direction of force A moving charges only parallel to the field B stationary charges only perpendicular to the field C stationary and moving charges parallel to the field D stationary and moving charges perpendicular to the field Space for working

1 marks

Answer: C

This question in 9702/11 May/June 2010

28 Two oppositely-charged parallel plates are arranged as shown. _ + An electron is released from rest from the surface of the negatively-charged plate. The electron travels from the negatively-charged plate towards the positively-charged plate. Which graph shows how the force F on the electron varies with its distance x from the negative plate? A B C D F F F F 00 00 00 00 x x x x Space for working

1 marks

Answer: D

This question in 9702/11 May/June 2010

27 Two oppositely-charged parallel plates are arranged as shown. _ + An electron is released from rest from the surface of the negatively-charged plate. The electron travels from the negatively-charged plate towards the positively-charged plate. Which graph shows how the force F on the electron varies with its distance x from the negative plate? A B C D F F F F 00 00 00 00 x x x x Space for working

1 marks

Answer: D

This question in 9702/13 May/June 2010

28 Which row describes the circumstances under which forces act on a charged particle in a uniform electric field? charged particle direction of force A moving charges only parallel to the field B stationary charges only perpendicular to the field C stationary and moving charges parallel to the field D stationary and moving charges perpendicular to the field

1 marks

Answer: C

This question in 9702/13 May/June 2010

28 The diagram shows a vertical uniform electric field in a vacuum. direction of electron flow electric field An electron gun injects a beam of electrons horizontally into the field. Which changes, if any, have occurred to the path and speed of the electrons by the time the beam leaves the field? path of electrons speed of electrons A deflected downwards increased B deflected downwards unchanged C deflected upwards increased D deflected upwards unchanged Space for working

1 marks

Answer: A

This question in 9702/12 Oct/Nov 2010

29 A very small oil drop of mass m carries a charge +q. – – – – – – – – oil drop + + + + + + + + The potential difference across the plates is V and the separation is d. The weight of the drop is balanced by the electric force. (Buoyancy forces may be considered to be negligible.) Which formula gives the charge on the drop? mgd mgV Vd V A q = B q = C q = mg D q = mgd V d

1 marks

Answer: A

This question in 9702/12 Oct/Nov 2010

28 Electrons are accelerated and then directed into the uniform electric field between two parallel plates in a vacuum. electrons What best describes the shape of the path followed by the electrons in the field? A a downwards curve along a line that is part of a circle B a downwards curve along a line that is not part of a circle C an upwards curve along a line that is part of a circle D an upwards curve along a line that is not part of a circle

1 marks

Answer: D

This question in 9702/13 Oct/Nov 2010

29 A charged particle is in the electric field between two horizontal metal plates connected to a source of constant potential difference, as shown. There is a force F on the particle due to the electric field. charged particle The separation of the plates is doubled. What will be the new force on the particle? F F A B C F D 2F 4 2 Space for working

1 marks

Answer: B

This question in 9702/13 Oct/Nov 2010

30 An electron is in an electric field of strength 5 × 104 V m–1. The field is the only influence on the electron. The mass and charge of an electron are known. Which quantity can be calculated without any more information? A the force on the electron B the momentum of the electron C the kinetic energy of the electron D the speed of the electron

1 marks

Answer: A

This question in 9702/13 Oct/Nov 2010

29 The diagram shows a charged particle as it approaches a pair of charged parallel plates in a vacuum. – – – – – – – – + + + + + + + + Which row describes the horizontal and vertical components of its motion as it travels between the plates? horizontal component vertical component A constant acceleration constant acceleration B constant acceleration constant velocity C constant velocity constant acceleration D constant velocity constant velocity

1 marks

Answer: C

This question in 9702/11 May/June 2011

30 Two parallel plates, a distance 25 mm apart, have a potential difference between them of 12 kV. What is the force on an electron when it is in the uniform electric field between the plates? A 4.8 × 10–20 N B 7.7 × 10–20 N C 4.8 × 10–17 N D 7.7 × 10–14 N Space for working

1 marks

Answer: D

This question in 9702/11 May/June 2011

30 The diagram shows two parallel metal plates connected to a d.c. power supply through a resistor. + – There is a uniform electric field in the region between the plates. Which change would cause a decrease in the strength of the electric field? A a small increase in the distance between the plates B a small increase in the potential difference between the plates C a small increase in the value of the resistor D a small increase to the area of both plates Space for working

1 marks

Answer: A

This question in 9702/12 May/June 2011

28 Two parallel plates, a distance 25 mm apart, have a potential difference between them of 12 kV. What is the force on an electron when it is in the uniform electric field between the plates? A 4.8 × 10–20 N B 7.7 × 10–20 N C 4.8 × 10–17 N D 7.7 × 10–14 N Space for working

1 marks

Answer: D

This question in 9702/13 May/June 2011

30 The diagram shows a charged particle as it approaches a pair of charged parallel plates in a vacuum. – – – – – – – – + + + + + + + + Which row describes the horizontal and vertical components of its motion as it travels between the plates? horizontal component vertical component A constant acceleration constant acceleration B constant acceleration constant velocity C constant velocity constant acceleration D constant velocity constant velocity

1 marks

Answer: C

This question in 9702/13 May/June 2011

31 Two horizontal parallel plate conductors are separated by a distance of 5.0 mm in air. The lower plate is earthed and the potential of the upper plate is +50 V. What is the electric field strength E at a point midway between the plates? A 1.0 × 104 V m–1 downwards B 1.0 × 104 V m–1 upwards C 2.0 × 104 V m–1 downwards D 2.0 × 104 V m–1 upwards Space for working

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2011

32 The diagram shows an insulating rod with equal and opposite point charges at each end. An electric field of strength E acts on the rod in a downwards direction. E +Q –Q Which row is correct? resultant force resultant torque A zero clockwise B downwards clockwise C zero anti-clockwise D downwards anti-clockwise

1 marks

Answer: C

This question in 9702/11 Oct/Nov 2011

29 The diagram shows a pair of parallel metal plates 4.0 mm apart connected to a 9.0 V battery. 4.0 mm 9.0 V What is the electric field strength between the plates? A 4.4 × 10–4 N C–1 B 3.6 × 10–2 N C–1 C 36 N C–1 D 2.3 × 103 N C–1

1 marks

Answer: D

This question in 9702/12 Oct/Nov 2011

30 Which path shows a possible movement of an electron in the electric field shown? A B electron beam D C Space for working

1 marks

Answer: A

This question in 9702/12 Oct/Nov 2011

31 The diagram shows an insulating rod with equal and opposite point charges at each end. An electric field of strength E acts on the rod in a downwards direction. E +Q –Q Which row is correct? resultant force resultant torque A zero clockwise B downwards clockwise C zero anti-clockwise D downwards anti-clockwise Space for working

1 marks

Answer: C

This question in 9702/13 Oct/Nov 2011

32 Two horizontal parallel plate conductors are separated by a distance of 5.0 mm in air. The lower plate is earthed and the potential of the upper plate is +50 V. What is the electric field strength E at a point midway between the plates? A 1.0 × 104 V m–1 downwards B 1.0 × 104 V m–1 upwards C 2.0 × 104 V m–1 downwards D 2.0 × 104 V m–1 upwards

1 marks

Answer: A

This question in 9702/13 Oct/Nov 2011

31 An electric field exists in the space between two charged metal plates. + X Y – Which graph shows the variation of electric field strength E with distance d from X along the line XY? A B C D E E E E 0 0 0 0 0 0 0 0 d d d d

1 marks

Answer: C

This question in 9702/12 May/June 2012

30 An electron is initially at rest in a uniform electric field. Which graph shows the variation with time of the velocity of the electron? A B velocity velocity 00 00 time time C D velocity velocity 00 00 time time Space for working

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2012

31 A charged particle is in the electric field between two horizontal metal plates connected to a source of constant potential difference, as shown. charged particle There is a force F on the particle due to the electric field. The separation of the plates is doubled. What will be the new force on the particle? A F B F C F D 2F 4 2

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2012

32 A charged particle moves in a uniform electric field between two parallel metal plates. To calculate the force acting on the particle due to the electric field, which quantity is not required? A particle charge B particle speed C plate separation D potential difference between the plates Space for working

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2012

33 A single proton travelling with a constant horizontal velocity enters a uniform electric field between two parallel charged plates. In the diagram, B shows the path taken by the proton. Which path is taken by a helium nucleus that enters the electric field at the same point and with the same velocity as the proton? A B C D

1 marks

Answer: C

This question in 9702/12 Oct/Nov 2012

30 The diagram shows two parallel plates. The plates are charged so that there is an electric field between them. P, Q and R are points which are 4 1 , 2 1 and 4 3 of the distance from the top plate to the bottom plate. P Q R What is the electric field strength at point P? A the same as that at point Q B twice that at point R C half that at point R D one third that at point Q

1 marks

Answer: A

This question in 9702/13 Oct/Nov 2012

31 A positive charge of 2.6 × 10–8 C is in an electric field of constant field strength 300 000 V m–1. How much work must be done on the charge in order to move it a distance of 4.0 mm in the opposite direction to the direction of the field? A 3.1 × 10–5 J B 2.0 × 10–3 J C 3.1 × 10–2 J D 2.0 J Space for working

1 marks

Answer: A

This question in 9702/13 Oct/Nov 2012

13 A small water droplet of mass 3.0 µg carries a charge of –6.0 × 10–11 C. The droplet is situated in the Earth’s gravitational field between two horizontal metal plates. The potential of the upper plate is +500 V and the potential of the lower plate is –500 V. +500 V water droplet – 2.0 mm with negative charge –500 V What is the motion of the droplet? A It accelerates downwards. B It remains stationary. C It accelerates upwards. D It moves upwards at a constant velocity.

1 marks

Answer: C

This question in 9702/11 May/June 2013

30 A beam of electrons is directed into an electric field and is deflected by it. Diagram 1 represents an electric field in the plane of the paper. Diagram 2 represents an electric field directed perpendicular to the plane of the paper. The lines A, B, C and D represent possible paths of the electron beam. All paths are in the plane of the paper. Which line best represents the path of the electrons inside the field? diagram 1 diagram 2 A B C D electric field electric field in the plane perpendicular to the of the paper plane of the paper electrons electrons Space for working

1 marks

Answer: B

This question in 9702/11 May/June 2013

31 Two oppositely-charged parallel plates are arranged as shown. _ + An electron is released from rest from the surface of the negatively-charged plate. The electron travels from the negatively-charged plate towards the positively-charged plate. Which graph shows how the force F on the electron varies with its distance x from the negative plate? A B C D F F F F 0 0 0 0 0 0 0 0 x x x x

1 marks

Answer: D

This question in 9702/11 May/June 2013

30 Two conducting layers of a liquid crystal display of a calculator are 8 µm apart. A 1.5 V cell is connected across the conducting layers when the calculator is switched on. What is the electric field strength between the layers? A 1.2 × 10–5 V m–1 B 0.19 V m–1 C 12 V m–1 D 1.9 × 105 V m–1 Space for working

1 marks

Answer: D

This question in 9702/12 May/June 2013

31 A positively-charged particle is projected into a uniform electric field. Which diagram represents the path of the particle in the electric field? A B electric field in plane of the paper electric field in plane of the paper + + C D electric field into paper electric field into paper + +

1 marks

Answer: A

This question in 9702/12 May/June 2013

12 The diagrams show a negative electric charge situated in a uniform electric field and a mass situated in a uniform gravitational field. – charge mass uniform electric field uniform gravitational field Which row shows the directions of the forces acting on the charge and on the mass? charge mass A – B – C – D – Space for working

1 marks

Answer: B

This question in 9702/13 May/June 2013

29 Two metal plates are held horizontal and parallel, 5.0 cm apart. The plates are at potentials of +100 V and +20 V. +100 V 5.0 cm +20 V What is the force experienced by an electron in the electric field between the plates? A 2.6 × 10–18 N B 3.8 × 10–18 N C 2.6 × 10–16 N D 3.8 × 10–16 N Space for working

1 marks

Answer: C

This question in 9702/13 May/June 2013

30 The diagram shows the path of a charged particle through a uniform electric field, having vertical field lines. electric path of field lines particle What could give a path of this shape? A a positive charge travelling left to right in a field directed downwards B a positive charge travelling right to left in a field directed downwards C a negative charge travelling right to left in a field directed upwards D a negative charge travelling left to right in a field directed downwards

1 marks

Answer: D

This question in 9702/13 May/June 2013

31 Two vertical conducting plates X and Y are positioned so that they are separated by a distance of 6.0 mm in air. A 60 V d.c. supply is connected as shown. plate plate X Y E 6.0 mm + – 60 V What is the electric field strength at E, a point midway between the plates? A 1.0 × 104 V m–1 towards X B 1.0 × 104 V m–1 towards Y C 2.0 × 104 V m–1 towards X D 2.0 × 104 V m–1 towards Y

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2013

32 Two parallel metal plates have a potential difference between them of 12 V. The distance between the plates is 1.0 mm. What are the electric field strength between the plates and the work done on a charge of +3.9 µC to move the charge from the negative plate to the positive plate? electric field work done strength / N C–1 / J A 12 4.7 × 10–5 B 12 47 C 12 000 4.7 × 10–5 D 12 000 47 Space for working

1 marks

Answer: C

This question in 9702/11 Oct/Nov 2013

31 Two vertical conducting plates X and Y are positioned so that they are separated by a distance of 6.0 mm in air. A 60 V d.c. supply is connected as shown. plate plate X Y E 6.0 mm + – 60 V What is the electric field strength at E, a point midway between the plates? A 1.0 × 104 V m–1 towards X B 1.0 × 104 V m–1 towards Y C 2.0 × 104 V m–1 towards X D 2.0 × 104 V m–1 towards Y

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2013

32 Two parallel metal plates have a potential difference between them of 12 V. The distance between the plates is 1.0 mm. What are the electric field strength between the plates and the work done on a charge of +3.9 µC to move the charge from the negative plate to the positive plate? electric field work done strength / N C–1 / J A 12 4.7 × 10–5 B 12 47 C 12 000 4.7 × 10–5 D 12 000 47 Space for working

1 marks

Answer: C

This question in 9702/12 Oct/Nov 2013

30 Two charged parallel metal plates produce an electric field. + Y X – A charged particle moves from X to Y. Which graph shows the variation of the force on the particle with distance from X along the line XY? A B C D force force force force 00 00 00 00 distance distance distance distance

1 marks

Answer: C

This question in 9702/13 Oct/Nov 2013

28 A horizontal beam of electrons is passed between two horizontal parallel plates, 2.0 cm apart, as shown. +4.0 V electron 2.0 cm beam – 4.0 V The upper plate has an electrical potential of +4.0 V, and the lower plate has an electrical potential of – 4.0 V. What is the force on each electron when between the plates? A 3.2 × 10–17 N downwards B 3.2 × 10–19 N upwards C 6.4 × 10–19 N downwards D 6.4 × 10–17 N upwards

1 marks

Answer: D

This question in 9702/11 May/June 2014

12 A tiny oil droplet with mass 6.9 × 10–13 kg is at rest in an electric field of electric field strength 2.1 × 107 N C–1, as shown. horizontal plate oil droplet The weight of the droplet is exactly balanced by the electrical force on the droplet. What is the charge on the droplet? A 3.3 × 10–20 C B –3.3 × 10–20 C C 3.2 × 10–19 C D –3.2 × 10–19 C Space for working

1 marks

Answer: D

This question in 9702/12 May/June 2014

29 Two oppositely-charged horizontal metal plates are placed in a vacuum. A positively-charged particle starts from rest and moves from one plate to the other plate, as shown. – + + Which graph shows how the kinetic energy EK of the particle varies with the distance x moved from the positive plate? A B C D EK EK EK EK 00 00 00 00 x x x x Space for working

1 marks

Answer: D

This question in 9702/12 May/June 2014

31 An electron enters a region of space where there is a uniform electric field E as shown. path of E electron Initially, the electron is moving parallel to, and in the direction of, the electric field. What is the subsequent path and change of speed of the electron? path of electron speed of electron A linear decreases B linear increases C parabolic decreases D parabolic increases Space for working

1 marks

Answer: A

This question in 9702/13 May/June 2014

32 Two parallel plates X and Y are separated by a distance d in a vacuum. There is a potential difference between the plates so that a uniform electric field is produced. plate X plate Y –q d A charge –q moves from rest from the surface of plate X and travels towards plate Y. When the charge reaches plate Y it has kinetic energy K. Which expression gives the electric field strength between the plates? q qd K Kd A B C D Kd K qd q Space for working

1 marks

Answer: C

This question in 9702/13 May/June 2014

28 The diagram shows two parallel horizontal metal plates. There is a potential difference V between the plates. +V liquid drop A small charged liquid drop, midway between the plates, is held in equilibrium by the combination of its weight and the electric force acting on it. The acceleration of free fall is g and the electric field strength is E. What is the polarity of the charge on the drop, and the ratio of charge to mass of the drop? charge polarity mass E A negative g g B negative E E C positive g g D positive E Space for working

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2014

29 The diagram shows two metal plates connected to a constant high voltage. d Which graph shows the variation of the electric field strength E midway between the two plates as the distance d between the two plates is increased? A B C D E E E E 0 0 0 0 0 d 0 d 0 d 0 d Space for working

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2014

28 The diagram shows two parallel horizontal metal plates. There is a potential difference V between the plates. +V liquid drop A small charged liquid drop, midway between the plates, is held in equilibrium by the combination of its weight and the electric force acting on it. The acceleration of free fall is g and the electric field strength is E. What is the polarity of the charge on the drop, and the ratio of charge to mass of the drop? charge polarity mass E A negative g g B negative E E C positive g g D positive E Space for working

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2014

29 The diagram shows two metal plates connected to a constant high voltage. d Which graph shows the variation of the electric field strength E midway between the two plates as the distance d between the two plates is increased? A B C D E E E E 0 0 0 0 0 d 0 d 0 d 0 d Space for working

1 marks

Answer: A

This question in 9702/12 Oct/Nov 2014

18 A positive charge experiences a force F when placed at point X in a uniform electric field. The charge is then moved from point X to point Y. Distances r and s are shown on the diagram. Y r uniform electric field F X s What is the change in the potential energy of the charge? A decreases by Fs B increases by Fs C decreases by Fr D increases by Fr Space for working

1 marks

Answer: A

This question in 9702/13 Oct/Nov 2014

32 The path of an electron with initial speed v in the uniform electric field between two parallel plates is shown. x The vertical deflection x is measured at the right-hand edge of the plates. The distance between the plates is halved. The potential difference between the plates remains the same. What will be the new deflection of the electron with the same initial speed v? A x B 2 x C 2x D 4x Space for working

1 marks

Answer: C

This question in 9702/13 Oct/Nov 2014

31 Two parallel metal plates, a distance of 2 mm apart, have a potential difference of 1000 V across them. What is the electric field strength between the plates? A 500 V m–1 B 50 000 V m–1 C 50 000 N C–1 D 500 000 N C–1

1 marks

Answer: D

This question in 9702/11 May/June 2015

32 An oil droplet has charge –q and is situated between two horizontal metal plates as shown in the diagram. +V d –q –V The separation of the plates is d. The droplet is observed to be stationary when the upper plate is at potential +V and the lower plate is at potential –V. For this to occur, what is the weight of the droplet? Vq 2 Vq Vd 2 Vd A B C D d d q q

1 marks

Answer: B

This question in 9702/11 May/June 2015

30 A charged oil drop of mass m, with n excess electrons, is held stationary in the uniform electric field between two horizontal plates separated by a distance d. V m d The voltage between the plates is V, the elementary charge is e and the acceleration of free fall is g. What is the value of n ? eV mgd meV gd A B C D mgd eV gd meV

1 marks

Answer: B

This question in 9702/12 May/June 2015

30 A molecule behaves as an electric dipole consisting of two equal point charges, of opposite sign, separated by a fixed distance. The molecule moves with constant horizontal velocity as it enters a vertical uniform electric field, as shown. +– molecule electric field The positive and negative charges of the molecule enter the field at the same time. Which row describes the velocity of the molecule in the field? horizontal component vertical component of velocity of velocity A constant increases B constant zero C increases increases D increases zero

1 marks

Answer: B

This question in 9702/13 May/June 2015

29 Two horizontal parallel plate conductors are separated by a distance of 20 mm in air. The upper plate is earthed and the potential of the lower plate is +100 V. 0 V P 20 mm +100 V What is the electric field strength at point P midway between the plates? A 5000 V m–1 downwards B 5000 V m–1 upwards C 10 000 V m–1 downwards D 10 000 V m–1 upwards

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2015

30 Three parallel metal plates of the same area are fixed with a separation of 2.0 cm between the top plate and the centre plate, and 1.0 cm between the centre plate and the bottom plate. The top plate is held at a potential of +500 V, the middle plate at +200 V and the bottom plate is earthed, as shown. +500 V X 2.0 cm +200 V 1.0 cm Y 0 V magnitude of force on an electron at X What is the value of the ratio ? magnitude of force on an electron at Y A 0.75 B 1.00 C 1.25 D 1.50

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2015

32 A particle situated between two parallel metal plates carries a charge of 8 × 10–19 C. The potential difference (p.d.) between the plates is 2000 V. A force of 3.2 × 10–13 N due to the electric field acts on the particle. What is the distance between the plates? A 5 mm B 8 mm C 5 cm D 8 cm

1 marks

Answer: A

This question in 9702/12 Oct/Nov 2015

29 Two parallel plates R and S are 2 mm apart in a vacuum. An electron with charge –1.6 × 10–19 C moves along a straight line in the electric field between the plates. The graph shows how the potential energy of the electron varies with its distance from plate R. +4.8 × 10–19 potential energy / J 0 0 1 2 distance / mm Which deduction is not correct? A The electric field between R and S is uniform. B The electric field strength is 3000 N C–1. C The force on the electron is constant. D The magnitude of the potential difference between R and S is 3 V.

1 marks

Answer: B

This question in 9702/13 Oct/Nov 2015

30 Two parallel, conducting plates with air between them are placed close to one another. The top plate is given a negative charge and the bottom one is earthed. Which diagram best represents the distribution of charges and the field between the plates? A B _ _ _ _ _ _ _ _ _ _ _ _ _ _ + + + + + + + C D _ _ _ _ _ _ _ _ _ _ _ _ _ _ + + + + + + +

1 marks

Answer: A

This question in 9702/13 Oct/Nov 2015

27 The diagram shows an electron in a uniform electric field. In which direction will the field accelerate the electron? electron A electric D B field C

1 marks

Answer: D

This question in 9702/12 Feb/March 2016

29 Two large parallel plates X and Y are placed a distance of 5.0 mm apart and connected to the terminals of a 200 V d.c. supply, as shown. X Y P 5.0 mm 200 V A small oil drop at P carries one excess electron. What is the magnitude of the electrostatic force acting on the oil drop due to the electric field between the plates? A 6.4 × 10–15 N B 6.4 × 10–18 N C 1.6 × 10–19 N D 4.0 × 10–24 N

1 marks

Answer: A

This question in 9702/12 Feb/March 2016

28 A charged particle is moving in a uniform electric field. For the motion of the particle due to the field, which quantity has a constant non-zero value? A acceleration B displacement C rate of change of acceleration D velocity

1 marks

Answer: A

This question in 9702/11 May/June 2016

30 Before a thunderstorm, the hairs on your head sometimes stand on end. A hair with mass 0.50 mg and charge 1.0 pC is supported by a force due to an electric field. Ignore any forces other than the weight of the hair and the electric force. What is the electric field strength? A 4.9 × 103 N C–1 B 4.9 × 105 N C–1 C 4.9 × 106 N C–1 D 4.9 × 109 N C–1

1 marks

Answer: C

This question in 9702/12 May/June 2016

31 Two parallel metal plates, 4.0 cm apart, are at electric potentials of 800 V and 2000 V. Points X, Y and Z are situated in the space between the plates at distances of 1.0 cm, 2.0 cm and 3.0 cm from the lower plate. 2000 V Z 3.0 cm metal 4.0 cm Y plates 2.0 cm X 1.0 cm 800 V What is the electric field strength, in V m–1, at X, Y and Z? X Y Z A 300 600 900 B 1100 1400 1700 C 3.0 × 104 3.0 × 104 3.0 × 104 D 5.0 × 104 5.0 × 104 5.0 × 104

1 marks

Answer: C

This question in 9702/12 May/June 2016

30 An electron is in an electric field of strength 5 × 104 V m–1. The field is the only influence on the electron. The mass and charge of an electron are known. Which quantity can be calculated without any more information? A the force on the electron B the momentum of the electron C the kinetic energy of the electron D the speed of the electron

1 marks

Answer: A

This question in 9702/13 May/June 2016

30 Which path shows a possible movement of an electron in the electric field shown? A B path of electron D C

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2016

32 Two large horizontal metal plates are separated by 4 mm. The lower plate is at a potential of –80 V. 4 mm –80 V Which potential should be applied to the upper plate to create an electric field of strength 60 000 V m–1 upwards in the space between the plates? A –320 V B –160 V C +160 V D +320 V

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2016

32 Two large horizontal metal plates are separated by 4 mm. The lower plate is at a potential of –80 V. 4 mm –80 V Which potential should be applied to the upper plate to create an electric field of strength 60 000 V m–1 upwards in the space between the plates? A –320 V B –160 V C +160 V D +320 V

1 marks

Answer: A

This question in 9702/13 Oct/Nov 2016

31 A constant potential difference is applied between two horizontal metal plates. A charged oil droplet is held stationary by the electric field between the plates. horizontal charged metal plates oil droplet As some of the oil evaporates, the droplet loses mass and starts to accelerate. Its charge remains constant. In which direction does the droplet accelerate, and which change needs to be made to the separation of the plates in order to stop this acceleration? direction of separation acceleration of the plates A downwards decrease B downwards increase C upwards decrease D upwards increase

1 marks

Answer: D

This question in 9702/12 Feb/March 2017

11 A particle with mass and charge is moving from left to right in a uniform gravitational field and a uniform electric field. The gravitational field is downwards. The gravitational force and the electric force on this particle act in opposite directions. What could be the sign of the charge on the particle and the direction of the electric field? direction of sign of charge electric field A negative down B negative up C positive left D positive right

1 marks

Answer: A

This question in 9702/11 May/June 2017

31 The diagram shows two parallel horizontal metal plates. The top plate is positively charged and the bottom plate is earthed. + liquid drop plates A small charged liquid drop, midway between the plates, is held in equilibrium by the combination of its weight and the electric force acting on it. The acceleration of free fall is g and the electric field strength is E. What is the polarity of the charge on the drop, and the ratio of charge to mass of the drop? charge polarity mass E A negative g g B negative E E C positive g g D positive E

1 marks

Answer: B

This question in 9702/11 May/June 2017

31 The path of an electron with initial speed v in the uniform electric field between two parallel plates is shown. plates x The vertical deflection x is measured at the right-hand edge of the plates. The distance between the plates is halved. The potential difference between the plates remains the same. What will be the new deflection of the electron with the same initial speed v ? A x B 2 x C 2x D 4x

1 marks

Answer: C

This question in 9702/12 May/June 2017

30 In a uniform electric field, which statement is correct? A All charged particles experience the same force. B All charged particles move with the same velocity. C All electric field lines are directed towards positive charges. D All electric field lines are parallel.

1 marks

Answer: D

This question in 9702/13 May/June 2017

31 A small charged sphere of mass 0.80 g hangs from a light thread inside a vertical uniform electric field of strength 2000 V m–1. The thread passes over two frictionless pulleys and a mass of 2.00 g hangs on the other end. pulleys + + + + + + 2.00 g mass electric field of charged sphere 2000 V m–1 of mass 0.80 g _ _ _ _ _ _ The sphere is in equilibrium. What is the charge on the sphere? A –5.9 µC B +0.60 µC C +5.9 µC D +9.8 µC

1 marks

Answer: C

This question in 9702/11 Oct/Nov 2017

32 An electron enters a region of space where there is a uniform electric field E as shown. path of E electron Initially, the electron is moving parallel to, and in the direction of, the electric field. What is the subsequent path and change of speed of the electron caused by the electric field? path of electron speed of electron A curved decreases B curved increases C linear decreases D linear increases

1 marks

Answer: C

This question in 9702/11 Oct/Nov 2017

31 The diagram shows two metal plates connected to a constant high voltage. d Which graph shows the variation of the electric field strength E midway between the two plates as the distance d between the two plates is increased? A B C D E E E E 0 0 0 0 0 d 0 d 0 d 0 d

1 marks

Answer: A

This question in 9702/12 Oct/Nov 2017

32 An electron moves between two points X and Y in a uniform electric field, as shown. Y uniform electric field X The distance between X and Y is 4.0 cm and the line XY is at an angle of 60° to the direction of the field. The field exerts the only force on the electron. The field strength is 100 N C–1. What is the change in the kinetic energy of the electron as it moves from X to Y? A – 4 eV B –2 eV C +2 eV D +4 eV

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2017

32 Lightning can occur between a charged cloud and the Earth’s surface when the electric field strength in the intervening atmosphere reaches 25 kN C–1. The diagram shows the electric field between the base of a cloud and the Earth’s surface. base of cloud – – – – – – – – – – – 2.0 km + + + + + + + + + + + Earth’s surface What is the minimum potential difference between the Earth and the base of a cloud, 2.0 km high, for lightning to occur? A 12.5 MV B 25 MV C 50 MV D 100 MV

1 marks

Answer: C

This question in 9702/13 Oct/Nov 2017

12 A charged oil drop is held stationary between two charged parallel plates. top plate charged oil drop bottom plate Which forces act on the oil drop? A both electric and gravitational B electric only C gravitational only D neither electric nor gravitational

1 marks

Answer: A

This question in 9702/12 Feb/March 2018

30 An electron passes into the space between two parallel plates that are 5.0 cm apart and which are maintained at electric potentials of +2000 V and –500 V, respectively. +2000 V electron 5.0 cm –500 V What is the electric force on the electron? A 1.6 × 10–15 N B 4.8 × 10–15 N C 6.4 × 10–15 N D 8.0 × 10–15 N

1 marks

Answer: D

This question in 9702/12 Feb/March 2018

31 Which statement about electric charges in a uniform electric field is not correct? A Electric charges of the same magnitude, whether positive or negative, experience the same magnitude of force when placed in the same uniform electric field. B The direction of the force on a positive charge placed in a uniform electric field is independent of the magnitude of the charge. C The magnitude of the force on a positive charge placed in a uniform electric field is proportional to the magnitude of the electric field strength. D The work done to move a positive charge a certain distance in a uniform electric field is independent of the direction of the movement.

1 marks

Answer: D

This question in 9702/12 Feb/March 2018

28 A particle has a charge of +2.0 mC and is in a vertical uniform electric field. An electric force of 1.0 × 10–2 N acts upwards on the particle. What is the electric field strength? A 0.20 V m–1 downwards B 0.20 V m–1 upwards C 5.0 V m–1 downwards D 5.0 V m–1 upwards

1 marks

Answer: D

This question in 9702/11 May/June 2018

29 A charged particle is in the electric field between two horizontal metal plates connected to a battery, as shown. There is a force F on the particle due to the electric field. charged particle The separation of the plates is doubled. What is the new force on the particle? A F B F C F D 2F 4 2

1 marks

Answer: B

This question in 9702/11 May/June 2018

30 Two large parallel metal plates X and Y are situated in a vacuum as shown. plate X + positively charged particle plate Y – Plates X and Y carry equal and opposite charges. What happens to the force on a positively charged particle as it moves from plate X to plate Y? A It decreases because the positively charged particle is moving away from the positively charged plate. B It decreases because the positively charged particle is moving in the direction of the electric field between the plates. C It increases because the positively charged particle is moving closer to a negatively charged plate. D It remains constant because the positively charged particle is in the uniform electric field between the plates.

1 marks

Answer: D

This question in 9702/12 May/June 2018

27 Two parallel metal plates are situated 20 cm apart in a vacuum. They are connected to two sources of potential difference as shown. proton 20 cm + + 800 V 300 V – – A proton is released in the space between the plates. What is the magnitude and direction of the acceleration of the proton? A 2.4 × 1011 m s–2 downwards B 2.4 × 1011 m s–2 upwards C 5.3 × 1011 m s–2 downwards D 5.3 × 1011 m s–2 upwards

1 marks

Answer: A

This question in 9702/13 May/June 2018

28 A particle having mass m and charge +q enters a uniform electric field with speed v. Initially, the particle is travelling at right-angles to the electric field. During its movement through the field, the particle is deflected through distance d, as shown. path of particle d region of uniform electric field A second particle of mass 2m, charge +q and speed v enters the electric field along the same path. What is the distance through which this particle is deflected in the electric field? d d A B C 2d D 4d 4 2

1 marks

Answer: B

This question in 9702/13 May/June 2018

31 A beam of electrons is directed into an electric field and is deflected by it. Diagram 1 represents an electric field in the plane of the paper. Diagram 2 represents an electric field directed perpendicular to the plane of the paper. The lines A, B, C and D represent possible paths of the electron beam. All paths are in the plane of the paper. Which line best represents the path of the electrons inside the field? diagram 1 diagram 2 A B C D electric field electric field into the paper in the plane and perpendicular to the of the paper plane of the paper electrons electrons

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2018

32 A charged particle of charge q and mass m is initially at rest in a uniform electric field. The field is produced by parallel metal plates separated by a distance d and having a potential difference V between them. What is an expression for the acceleration of the charged particle? md mV qd qV A B C D qV qd mV md

1 marks

Answer: D

This question in 9702/11 Oct/Nov 2018

11 A positively-charged particle of negligible mass, moving at constant velocity v in a vacuum, enters a uniform electric field between two parallel plates, as shown. positive plate v + negative plate A short time later, the particle is at the position shown. positive plate negative plate Which diagram represents the force or forces acting on the particle? A B C D

1 marks

Answer: D

This question in 9702/12 Oct/Nov 2018

32 Two parallel metal plates are connected to a d.c. supply, as shown. P The two plates are moved towards each other at constant speed. It may be assumed that the electric field between the plates is uniform. Point P is mid-way between the two plates. Which graph shows the variation with time t of the electric field strength E at point P? A B C D E E E E 0 0 0 0 0 t 0 t 0 t 0 t

1 marks

Answer: D

This question in 9702/12 Oct/Nov 2018

30 Two parallel metal plates are at electric potentials of +800 V and +1300 V. Which diagram best represents the electric field between the metal plates? A B +800 V +1300 V +800 V +1300 V C D +800 V +1300 V +800 V +1300 V

1 marks

Answer: B

This question in 9702/13 Oct/Nov 2018

31 The diagram shows two metal plates P and Q. There is a potential difference of 700 V between the plates. Plate Q is earthed. –700 V plate P 5.0 mm R plate Q 0 V What is the magnitude and direction of the electric field at point R? A 1.4 × 102 N C–1 from P towards Q B 1.4 × 102 N C–1 from Q towards P C 1.4 × 105 N C–1 from P towards Q D 1.4 × 105 N C–1 from Q towards P

1 marks

Answer: D

This question in 9702/13 Oct/Nov 2018

30 Two horizontal parallel plate conductors are separated by a distance of 5.0 mm in air. The lower plate is earthed and the potential of the upper plate is +50 V. What is the electric field strength E at a point midway between the plates? A 1.0 × 104 V m–1 downwards B 1.0 × 104 V m–1 upwards C 2.0 × 104 V m–1 downwards D 2.0 × 104 V m–1 upwards

1 marks

Answer: A

This question in 9702/12 Feb/March 2019

8 A positive charge of 2.6 × 10–8 C is in a uniform electric field of field strength 300 000 V m–1. How much work must be done on the charge in order to move it a distance of 4.0 mm in the opposite direction to the direction of the field? A 3.1 × 10–5 J B 2.0 × 10–3 J C 3.1 × 10–2 J D 2.0 J

1 marks

Answer: A

This question in 9702/11 May/June 2019

32 An electron is situated in a vacuum between two charged plates, as shown. – – – – – – – – electron + + + + + + + + Which statement describes the motion of the electron due to the uniform electric field? A It moves downwards with a constant acceleration. B It moves downwards with zero acceleration. C It moves upwards with a constant acceleration. D It moves upwards with a decreasing acceleration.

1 marks

Answer: A

This question in 9702/12 May/June 2019

10 A uniform electric field is created by two parallel vertical plates. A positively charged particle is in the vacuum between the plates, as shown. – + – positively + charged – particle + – + – + – + – + – + Which statement is correct? A The electric field makes the particle move towards the negative plate with a constant speed. B The electric field makes the particle move towards the negative plate with a constant acceleration. C The electric field produces a uniform rate of decrease in the particle’s acceleration. D The electric field produces a uniform rate of increase in the particle’s acceleration.

1 marks

Answer: B

This question in 9702/13 May/June 2019

10 A positively charged oil droplet falls in air in a uniform electric field that is vertically upwards. The droplet has a constant terminal speed v0 and the electric field strength is E. The magnitude of the force due to air resistance acting on the droplet is proportional to the speed of the droplet. Which graph shows the variation with E of v0? A B C D v0 v0 v0 v0 0 0 0 0 0 E 0 E 0 E 0 E

1 marks

Answer: A

This question in 9702/12 Oct/Nov 2019

30 A charged oil drop of mass m, with n excess electrons, is held stationary in the uniform electric field between two horizontal plates separated by a distance d. V m d The voltage between the plates is V, the elementary charge is e and the acceleration of free fall is g. What is the value of n ? eV mgd meV gd A B C D mgd eV gd meV

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2019

32 A uniform electric field is represented by five horizontal field lines. P Q P and Q are two points in the field. The field causes a positively charged particle in a vacuum to move from P to Q. Which statement must be correct? A The acceleration of the particle between P and Q is increasing. B The kinetic energy of the particle at P is the same as the kinetic energy of the particle at Q. C The force on the particle at Q is greater than the force on the particle at P. D Work is done on the particle as it moves from P to Q.

1 marks

Answer: D

This question in 9702/13 Oct/Nov 2019

31 A negatively charged oil drop is held stationary, equidistant between two plates connected to a high voltage supply, as shown. + oil drop – Which change would not increase the upward electrical force on the drop? A decreasing the distance between the plates whilst keeping the drop equidistant from them B increasing the amount of negative charge on the drop C increasing the supply voltage D moving the drop closer to the positive plate

1 marks

Answer: D

This question in 9702/12 Feb/March 2020

32 A charged particle is in a vacuum between two horizontal metal plates as shown. charged particle horizontal plate +300 V 2.0 cm horizontal plate 0 V The acceleration of the particle is 7.15 × 1011 m s–2 downwards. The particle has a mass of 3.34 × 10–27 kg. What is the charge on the particle? A +1.6 × 10–19 C B –1.6 × 10–19 C C +1.6 × 10–17 C D –1.6 × 10–17 C

1 marks

Answer: A

This question in 9702/11 May/June 2020

10 The diagrams show a negative electric charge situated in a uniform electric field and a mass situated in a uniform gravitational field. – charge mass uniform electric field uniform gravitational field Which row shows the directions of the forces acting on the charge and on the mass? charge mass A – B – C – D –

1 marks

Answer: B

This question in 9702/12 May/June 2020

32 A charged oil droplet of mass m is falling, initially freely, in a vacuum between two horizontal metal plates that are separated by a distance x. A potential difference (p.d.) V is then applied across the plates. This results in the oil droplet continuing to accelerate downwards but with a reduced acceleration a. The polarity of the applied p.d. is then reversed so that the direction of the electric force on the droplet is reversed. This results in the downwards acceleration of the oil droplet increasing to 3a. What is the magnitude of the charge on the oil droplet? max 2 max 3 max 4 max A B C D V V V V

1 marks

Answer: A

This question in 9702/12 May/June 2020

32 A negatively charged oil drop of mass m is between two horizontal parallel metal plates a distance d apart. oil drop mass m horizontal + metal plates d – When the potential difference (p.d.) between the plates is V1 the oil drop rises at a constant speed. When the p.d. is decreased to a value V2 the oil drop falls at the same constant speed. Air resistance acts on the drop when it is moving. The upthrust on the drop is negligible. The acceleration of free fall is g. What is the charge on the oil drop? mdg mdg 2 mdg 2 mdg A B C D V – V V + V V – V V + V 1 2 1 2 1 2 1 2

1 marks

Answer: D

This question in 9702/13 May/June 2020

11 A particle is situated at rest between two metal plates X and Y. A potential difference (p.d.) is then applied across the plates and produces the electric field shown. X Y electric particle field The particle moves towards plate X when the p.d. is applied. What could be the particle? A alpha-particle B electron C neutron D proton

1 marks

Answer: B

This question in 9702/11 Oct/Nov 2020

31 An oil drop has mass m and charge q. The drop is held stationary in an electric field between two parallel horizontal plates, a distance d apart, as shown. oil drop V d The potential difference between the plates is V and the acceleration of free fall is g. q of the oil drop? What is the charge-to-mass ratio m gd V gV d A B C D V dg d Vg

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2020

31 A molecule behaves as an electric ‘dipole’ consisting of two equal point charges of opposite sign, separated by a fixed distance. The molecule moves with constant horizontal velocity as it enters a vertical uniform electric field, as shown. +– molecule electric field The positive and negative charges of the molecule enter the field at the same time. What describes the effect of the electric field on the velocity of the molecule? horizontal component vertical component of velocity of velocity A constant increases B constant zero C increases increases D increases zero

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2020

32 Two parallel metal plates are connected to a battery of negligible internal resistance. metal plates One of the plates is slowly moved towards the other. Which row is correct? electric field strength potential difference between the plates between the plates A decreases constant B increases constant C decreases increases D increases increases

1 marks

Answer: B

This question in 9702/12 Oct/Nov 2020

31 A stationary particle is in an electric field. The only force on the particle is that from the electric field. In which case is the electric field strength 5.0  105 V m–1? A a force of 1.6  10–14 N acting on an electron B a force of 3.2  10–14 N acting on an alpha-particle C a force of 8.0  10–14 N acting on an alpha-particle D a force of 8.0  10–14 N acting on a proton

1 marks

Answer: D

This question in 9702/13 Oct/Nov 2020

32 A constant potential difference is applied between two horizontal metal plates. A charged oil droplet is held stationary by the electric field between the plates. horizontal charged metal plates oil droplet As some of the oil evaporates, the droplet loses mass and starts to accelerate. Its charge remains constant. In which direction does the droplet accelerate, and which change needs to be made to the separation of the plates in order to stop this acceleration? direction of separation acceleration of the plates A downwards decrease B downwards increase C upwards decrease D upwards increase

1 marks

Answer: D

This question in 9702/13 Oct/Nov 2020

11 A particle with mass moves in a horizontal straight line through a uniform electric field in a vacuum. The electric field is vertical. horizontal path of particle electric field particle direction of gravitational field There is a significant gravitational effect on the motion of the particle. What could be the direction of the electric field and the sign of the charge, if any, on the particle? electric field sign of charge direction A downwards negative B downwards positive C upwards negative D upwards no charge

1 marks

Answer: A

This question in 9702/12 Feb/March 2021

31 The diagram shows a thundercloud whose base is 500 m above the ground. 500 m The potential difference between the base of the cloud and the ground is 200 MV. A raindrop with a charge of 4.0 × 10–12 C is in the region between the cloud and the ground. What is the electrical force on the raindrop? A 1.6 × 10–6 N B 8.0 × 10–4 N C 1.6 × 10–3 N D 0.40 N

1 marks

Answer: A

This question in 9702/12 Feb/March 2021

11 A charged oil drop is held stationary between two charged parallel plates. top plate charged oil drop bottom plate Which forces act on the oil drop? A both electric and gravitational B electric only C gravitational only D neither electric nor gravitational

1 marks

Answer: A

This question in 9702/11 May/June 2021

30 What is the electric field strength in a region where a proton accelerates at 2.00 m s–2 due to the field? A 11.4 pV m–1 B 5.22 nV m–1 C 10.4 nV m–1 D 20.9 nV m–1

1 marks

Answer: D

This question in 9702/11 May/June 2021

31 An oil drop of mass 2.6  10–15 kg and with a charge of – 4.8  10–19 C is in a vacuum between two horizontal plates. The plates have a separation of 2.0 cm and a potential difference (p.d.) between them of 1200 V, as shown. +1200 V oil drop plates 2.0 cm 0 V Which statement describes the motion of the oil drop? A It is stationary. B It has a downward acceleration of 9.7 m s–2. C It has an upward acceleration of 1.3 m s–2. D It has an upward acceleration of 11 m s–2.

1 marks

Answer: C

This question in 9702/11 May/June 2021

31 A particle has a charge of +2.0 mC and is in a vertical uniform electric field. An electric force of 1.0  10–2 N acts upwards on the particle. What is the electric field strength? A 0.20 V m–1 downwards B 0.20 V m–1 upwards C 5.0 V m–1 downwards D 5.0 V m–1 upwards

1 marks

Answer: D

This question in 9702/13 May/June 2021

32 The diagram shows two parallel metal plates connected to a d.c. power supply through a resistor. + – There is a uniform electric field in the region between the plates. Which change would cause a decrease in the strength of the electric field? A a small increase in the distance between the plates B a small increase in the potential difference between the plates C a small increase in the resistance of the resistor D a small increase to the area of both plates

1 marks

Answer: A

This question in 9702/13 May/June 2021

31 Three parallel metal plates of the same area are fixed with a separation of 2.0 cm between the top plate and the middle plate, and 1.0 cm between the middle plate and the bottom plate. The top plate is held at a potential of +500 V, the middle plate at +200 V and the bottom plate is earthed, as shown. +500 V X 2.0 cm +200 V 1.0 cm Y 0 V magnitude of force on an electron at X What is the value of the ratio ? magnitude of force on an electron at Y A 0.75 B 1.00 C 1.25 D 1.50

1 marks

Answer: A

This question in 9702/11 Oct/Nov 2021

31 Two parallel metal plates are at electric potentials of +800 V and +1300 V. Which diagram best represents the electric field between the metal plates? A B +800 V +1300 V +800 V +1300 V C D +800 V +1300 V +800 V +1300 V

1 marks

Answer: B

This question in 9702/13 Oct/Nov 2021

32 An electron is in a uniform electric field of field strength 1500 V m–1. What is the acceleration of the electron due to the electric field? A 8.5  10–9 m s–2 B 1.6  10–5 m s–2 C 1.4  1011 m s–2 D 2.6  1014 m s–2

1 marks

Answer: D

This question in 9702/13 Oct/Nov 2021