Mass and weight — Paper 4 · IGCSE Sciences - Co-ordinated (Double) 0654

12 Fig. 12.1 shows a solar-powered golf cart, with solar cells on the roof. Fig. 12.1 The solar cells produce electrical energy using solar energy. The Sun is the source of this energy. (a) Name two energy resources that do not have the Sun as their source of energy. 1 … 2 … [1] (b) During the golf cart’s journey, the temperature in the tyres increases. The volume of air in the tyres does not change. Explain in terms of molecules the effect on the pressure of a gas due to an increase in temperature at constant volume. … … … … [2] (c) The golf cart often travels across sloping fields so stability is important in its design. Fig. 12.2 shows the cart on a slope. X Fig. 12.2 The centre of mass of the golf cart is shown by the letter X. State the effect of raising the centre of mass of the golf cart on its stability. … … [1] (d) A spectator takes a photograph of a golfer with a camera. The camera uses a thin converging lens to focus light rays onto the light sensor inside the camera. (i) Complete the ray diagram in Fig. 12.3 to show this. camera lens light rays light from golfer sensor Fig. 12.3 [1] (ii) The lens is made from glass. Glass has a refractive index of 1.33. Define refractive index in terms of the speed of light in a vacuum and in glass. … … [1] (iii) The image produced by the lens on the light sensor is a real image. Describe the difference between a real image and a virtual image. … … [1] (e) Describe in terms of the forces between the atoms why solids have a fixed shape. … … [1] [Total: 8]

8 marks

Mark scheme: 12(a) any two from geothermal nuclear tidal ; 1 12(b) increase in pressure because molecules are moving faster / have more KE ; collide with walls of tyre more frequently / at greater speed / with greater force ; 2 12(c) less stable ; 1 12(d)(i) two straight rays brought to a focus on the light sensor ; 1 12(d)(ii) speed of light in vacuum ÷ speed of light in glass ; 1 12(d)(iii) real image can be projected onto a screen / is formed where the light rays converge ; virtual image is one from which the light rays appear to come from that image ; max 1 12(e) (fixed shape because) strong forces (keep particles in regular / fixed arrangement) ; 1

This question in 0654/41 May/June 2019

3 (a) Fig. 3.1 shows the forces acting on an aircraft. P S Q R Fig. 3.1 Four forces P, Q, R and S are shown. (i) Compare the sizes of forces Q and S when the aircraft is accelerating. … … [1] (ii) State which force is the weight of the aircraft. … [1] (iii) Complete the sentence below to describe the relationship between the mass and the weight of an object. Weight is the effect of a … field on a mass. [1] (b) Fig. 3.2 is the speed-time graph for an aircraft during take-off. 70 60 speed m / s 50 40 30 20 10 0 0 10 20 30 40 50 time / s Fig. 3.2 Calculate the acceleration between 5 s and 45 s. Show your working. State the units of your answer. acceleration = … units … [3] (c) State the two types of energy gained as the aircraft continues to accelerate and gain height after take-off. 1 … energy 2 … energy [1] (d) The aircraft engines are noisy. Sound waves from the engines pass through the air as a series of compressions and rarefactions. (i) State what is meant by a compression. … … [1] (ii) Describe the wavelength of a sound wave in terms of compressions. … … [1] [Total: 9]

9 marks

Mark scheme: 3(a)(i) Q is greater than S ; 1 3(a)(ii) R ; 1 3(a)(iii) gravitational ; 1 3(b) (acceleration =) change in speed/time or 50 / 40 ; = 1.3 / 1.25 ; m/s2 ; 3 3(c) kinetic and gravitational potential energy ; 1 3(d)(i) region of high pressure / where particles are closer together ; 1 3(d)(ii) distance between two successive compressions ; 1

This question in 0654/43 May/June 2019

12 A fishing boat floats on the sea. (a) A heavy anchor is dropped from the boat and accelerates as it falls through the water to the sea bed. Name the downward force that makes the anchor accelerate. … [1] (b) The boat has a small generator to generate electricity. Fig. 12.1 shows a simple generator. N S Fig. 12.1 (i) On Fig. 12.1 label a slip ring with the letter R. [1] (ii) Describe how the use of slip rings produces an alternating voltage output from the rotating coil. … … … [2] (iii) On the grid in Fig. 12.2, sketch a graph of voltage output against time for the generator, when the coil is rotating at a constant speed. voltage output time Fig. 12.2 [2] (c) An electric heater on the boat uses the electricity generated at 240 V. The current passing through the heater is 20 A. Calculate the charge passing through the heater in one hour. State the unit of your answer. charge = … unit … [3] (d) A fisherman on the boat is using a pair of binoculars to look at the sea. Binoculars use glass prisms to reflect light. Fig. 12.3 shows part of a pair of binoculars. A ray of light is shown entering and leaving. glass prism light ray entering light ray leaving Fig. 12.3 On Fig. 12.3, complete the ray diagram to show the path of the light ray through the two prisms. [1] [Total: 10]

10 marks

Mark scheme: 12(a) weight ; 1 12(b)(i) slip rings labelled correctly ; 1 12(b)(ii) induced voltage changes every half turn ; same side of coil remains connected to same slip ring ; 2 12(b)(iii) approx. sine curve ; regular frequency and amplitude ; 2 12(c) (charge =) current × time or 20 × 1 × 60 × 60 ; 72 000 ; C ; 3 12(d) ray drawn correctly through first prism and through second prism ; 1

This question in 0654/42 Oct/Nov 2019

9 (a) The information booklet about an oven states that the weight of the oven is 45 kg. Explain why this statement is incorrect. … … [1] (b) (i) Fig. 9.1 shows information on a label attached to the electric oven. 240 V 6000 W Fig. 9.1 Use Fig. 9.1 to calculate the maximum working current of the oven. current = … A [2] (ii) The oven has its own fuse. Use your answer to (b)(i) to explain why a fuse rated at 13 A is not suitable for use in the oven circuit. … … … [1] (c) A thermocouple is used to measure the temperature inside the oven. Describe the structure of a thermocouple. You may draw a diagram if it helps your answer. … … … [2] (d) Some water is heated in a dish in the oven. As the water is heated, some of the water evaporates. Eventually the water begins to boil. Describe two differences between evaporation and boiling. 1 … … 2 … … [2] [Total: 8]

8 marks

Mark scheme: 9(a) mass is measured in kg / weight is measured in newtons; 1 9(b)(i) I = P / V or working 6000 / 240; current = 25 (A); 2 9(b)(ii) fuse rating should be higher than working current / fuse will blow ; 1 9(c) two different metals ; joined together / to make junction(s) ; 2 Question Answer Marks 9(d) evaporation can occur at any temperature / boiling occurs at the boiling point ; evaporation happens only at the surface / boiling occurs throughout the liquid ; during boiling, all / most, molecules have enough energy to leave / evaporation only lets the molecules with the greatest kinetic energy escape ; evaporation can occur using the internal energy of the system / boiling requires a(n external) source of heat ; evaporation is a slow process / boiling is a rapid process ; evaporation produces cooling / boiling does not produce cooling ; max 2 2

This question in 0654/42 Oct/Nov 2020

12 Fig. 12.1 shows a speed-time graph for a train. 35 30 speed m / s 25 20 15 10 5 0 0 50 100 150 200 time / s Fig. 12.1 (a) Use Fig. 12.1 to calculate the distance travelled by the train in the first 100 s. distance = … m [2] (b) Use Fig. 12.1 to calculate the acceleration of the train from 0 s to 100 s. acceleration = … m / s2 [2] (c) Use Fig. 12.1 to describe the motion of the train from 100 s to 200 s. … … … … … [3] (d) Fig. 12.2 shows the forces acting on the train when it is travelling at constant speed. 1.96 × 106 N P 2.60 × 104 N 1.96 × 106 N Fig. 12.2 (i) State the magnitude of the force P. … [1] (ii) Calculate the mass of the train. The gravitational field strength on Earth, g, is 10 N / kg. mass = … kg [1] (e) The train is made of steel painted dark grey. On sunny days, the inside of the train can get very hot. Explain why painting the train white would reduce the heating effect. … … [1] [Total: 10]

10 marks

Mark scheme: 12(a) using area under graph ; 500 (m) ; 2 12(b) (a =) (v–u) ÷ t / 10÷100 ; 0.1 (m / s2) ; 2 12(c) constant acceleration initially ; non-uniform acceleration / rate of acceleration decreases, at 135 s ; then constant speed from 160s ; 3 12(d)(i) 2.60 × 104 (N) ; 1 12(d)(ii) (m = W÷g / 1.96 × 106 ÷ 10 =) 1.96 × 105 (kg) ; 1 12(e) white paint absorbs less thermal / infra-red radiation or reflects more thermal / infra-red radiation ; 1

This question in 0654/42 Feb/March 2021

6 Some students are investigating moments and turning effects. Fig. 6.1 shows a beam of uniform density in equilibrium. The beam has a mass of 20 g on one end and a stone on the other. 0.19 m 0.25 m 20 g Fig. 6.1 (a) State the meaning of the word equilibrium. … … [1] (b) (i) Calculate the weight of the 20 g mass. gravitational field strength g = 10 N / kg weight = … N [3] (ii) Calculate the mass of the stone. State the unit for your answer. mass = … unit … [4] (c) Describe a method for determining the volume of an irregular object like the stone. … … … … … [2] [Total: 10]

10 marks

Mark scheme: 6(a) no resultant force and no resultant turning effect ; 1 6(b)(i) 0.02 or 20 × 10–3 (kg) ; (W =) mg or 0.02 × 10 ; 0.2 (N) ; 3 6(b)(ii) clockwise moment = force × distance or 0.2 × 0.25 or 0.05 ; anti-clockwise moment = clockwise moment ; F = 0.05 ÷ 0.19 or 0.263 / m = 0.263 ÷ 10 or 0.026 (kg) or 26 (g) ; g / kg ; 4 6(c) immerse in water ; measure volume of displaced water ; 2

This question in 0654/41 Oct/Nov 2021

9 Fig. 9.1 shows a helium filled balloon attached to a spring. The spring is attached to a table top to stop the balloon moving upwards. The balloon is in equilibrium. Fig. 9.1 (a) The helium filled balloon has a mass of 6.5 g. (i) Calculate the weight of the helium filled balloon. gravitational field strength g = 10 N / kg weight = … N [2] (ii) The balloon causes the spring to extend by 0.50 cm. The spring constant of the spring is 0.45 N / cm. Calculate the force on the spring. force = … N [2] (iii) State the total downwards force acting on the balloon. force = … N [1] (b) A student places the balloon under an infrared lamp to warm the helium gas. (i) Suggest the colour of balloon which will give the greatest rate of increase in gas temperature. Explain your answer. colour … explanation … … [2] (ii) Explain why the size of the balloon increases as it is heated. … … … … … [3] [Total: 10]

10 marks

Mark scheme: 9(a)(i) (W =) mg or 0.0065 × 10 ; 0.065 (N) ; 2 9(a)(ii) (F =) kx or 0.45 × 0.50 ; 0.225 (N) ; 2 9(a)(iii) 0.29 (N) ; 1 9(b)(i) black ; absorbs more, radiation / heat, than other colours ; 2 9(b)(ii) molecules, gain kinetic energy / speed up / move faster ; molecules collide more often with the balloon / so the molecules exert a larger force on the inside of the balloon ; so the molecules exert higher pressure ; 3

This question in 0654/42 Oct/Nov 2021

6 Fig. 6.1 shows a baby elephant born in a wildlife sanctuary. The elephant is undergoing a routine health check. 480 kg Fig. 6.1 (a) Explain what is wrong with the statement “the weight of the elephant is 480 kg”. … … [1] (b) The top speed for a fully grown elephant is 11 m / s. Calculate the maximum distance that can be covered by an elephant in 120 seconds. distance = … m [2] (c) The wildlife sanctuary uses enclosures to keep the elephants safe. Fig. 6.2 shows an enclosure surrounded by four lamps. Fig. 6.2 The lamps are connected in parallel. A switch controls the a.c. power supply to the lamps. (i) Complete the circuit diagram to show the lamps connected in parallel. Include the switch in your diagram. The a.c. power supply has been drawn for you. a.c. power supply [2] (ii) The current through the a.c. power supply is 16 A. Draw a circle around the correct current through each lamp. 2 A 4 A 16 A 32 A 64 A [1] (iii) The potential difference across each lamp is 240 V. Calculate the power output of each lamp. power = … W [2] [Total: 8]

8 marks

Mark scheme: 6(a) 480 kg is the mass / weight should be in Newtons ; 1 6(b) (d =) vxt or 11  120 ; 1320 (m) ; 2 6(c)(i) switch controls all lamps ; 4 lamps in parallel and all else correct ; 2 6(c)(ii) 4 A ; 1 6(c)(iii) (P =) IV / 4  240 ; 960 (W) ; 2

This question in 0654/42 May/June 2022

12 Radon is a radioactive gas which occurs naturally in rocks and soil. (a) Radon-222 (22286Ra) is an unstable isotope which decays by emitting an alpha particle. (i) Use the correct nuclide notation to show the decay of radon-222. 222 … … 86Ra … Po + … α [2] (ii) Draw lines to match an alpha particle with its correct characteristics. One line has been drawn as an example. has a charge of 0 has a charge of –1 has a charge of +2 has a mass of 0 has a mass of 2 alpha particle has a mass of 4 has a low ionizing ability has a high ionizing ability can penetrate paper can penetrate aluminium can penetrate lead [1] (iii) Complete Fig. 12.1 to show the path of an alpha particle as it travels through the electric field between two charged plates. [1] + – + – + – + – + – alpha Fig. 12.1 (b) A sample of radon gas is stored in a container with a fixed volume. (i) Explain, in terms of the molecular motion, why the pressure in the radon gas increases when the temperature is increased. … … … … … [3] (ii) The volume of the container is 0.050 m3. The density of the radon gas is 9.7 kg / m3. Calculate the weight of the radon gas in the container. The gravitational field strength, g, is 10 N / kg. weight = … N [3] [Total: 10]

10 marks

Mark scheme: 12(a)(i) 222 86Ra → 21884 Po + 42 2 Po correct ;  correct ; 12(a)(ii) 1 has a mass of 4 and has a high ionising ability ; 12(a)(iii) 1 line curved to the right ; 12(b)(i) kinetic energy/speed of atoms increases ; 3 atoms collide with walls of container more often ; which exerts a larger force per unit area ; 12(b)(ii) (m =) V ; 3 (m = 9.7  0.05) 0.485 (kg) ; (W = mg = 0.485  10 =) 4.9 (N) ;

This question in 0654/42 Oct/Nov 2023

3 Fig. 3.1 shows a sea turtle. Fig. 3.1 (a) (i) On Fig. 3.1, draw an arrow to show the direction of the weight force acting on the sea turtle. Label your arrow with the letter W. [1] (ii) Complete the sentence to describe weight. Weight is a force caused by the effect of a … field on a … . [1] (b) The sea turtle travels a distance of 1200 km in 20 days. Calculate the average speed of the sea turtle. Give your answer in km / h. average speed = … km / h [3] (c) A team of scientists fits a tracker unit to the sea turtle to monitor its location. The tracker unit sends a signal using radio waves each time the sea turtle moves to the surface of the water. (i) Radio waves are part of the electromagnetic spectrum. Complete the sentences to compare radio waves to visible light. Radio waves have a … frequency and a … wavelength than visible light. Radio waves and visible light both travel at … m / s in a vacuum. [2] (ii) The radio waves emitted by the tracker unit have a frequency of 1.5 × 109 Hz. Calculate the wavelength of the radio waves. wavelength = … m [2] (iii) The tracker unit uses a battery with an electromotive force (e.m.f.) of 11 V that provides a power output of 22 mW. The battery can transfer a total charge of 24 000 C before it needs replacing. Calculate the time for which the battery operates before it needs replacing. time = … s [4] [Total: 13]

13 marks

Mark scheme: 3(a)(i) downwards arrow labelled W ; 1 3(a)(ii) gravitational AND mass ; 1 3(b) (t=) 480 (hrs) ; (v=) d / t OR 1200 / 480 ; (v=) 2.5 (km / h) ; 3 3(c)(i) lower AND longer / bigger ; 3  108 ; 2 3(c)(ii) (=) v / f OR 3  108 / 1.5  109 ; (=) 0.20 (m) ; 2 Question Answer Marks 3(c)(iii) (P=) 0.022 (W) ; (I=) P / V OR 0.022 / 11 OR 0.002 ; (t=) Q / I OR 24000 / 0.002 ; (t=) 1.2  107 (s) ; 4

This question in 0654/42 May/June 2024