Transfer of thermal energy — Paper 2 · IGCSE Sciences - Co-ordinated (9-1) 0973

32 Two identical metal containers are painted. One is painted dull black and the other is painted shiny silver. They contain equal volumes of water and are placed outside on a sunny day. The temperature of the water in the black container increases more quickly than the temperature of the water in the silver container. Why does this happen? A The black container is the better absorber of radiation from the Sun. B The black container is the better conductor of heat. C The black container is the better emitter of radiation. D The black container is the better reflector of radiation from the Sun.

1 marks

Answer: A

This question in 0973/21 May/June 2019

34 A hot water tank is fitted with two identical heaters P and Q. Heater P is fitted above heater Q as shown. The tank is full of cold water. heater P heater Q When only heater Q is switched on, it takes a long time to heat the tank of water to 60 C. What happens to the cold water when only heater P is switched on? A All the water reaches 60 C in less time. B All the water reaches 60 C in the same time. C The water below heater P reaches 60 C in less time. D The water above heater P reaches 60 C in less time.

1 marks

Answer: D

This question in 0973/21 May/June 2020

31 A hot water tank is fitted with two identical heaters P and Q. Heater P is fitted above heater Q as shown. The tank is full of cold water. heater P heater Q When only heater Q is switched on, it takes a long time to heat the tank of water to 60 °C. What happens to the cold water when only heater P is switched on? A All the water reaches 60 °C in less time. B All the water reaches 60 °C in the same time. C The water below heater P reaches 60 °C in less time. D The water above heater P reaches 60 °C in less time.

1 marks

Answer: D

This question in 0973/22 May/June 2020

33 Three identical metal cans X, Y and Z are painted. X is painted dull black, Y is painted dull white and Z is painted shiny silver. All three cans are filled with the same amount of water at 100 C. They are left in a cool room for the same amount of time. Which row shows possible temperatures of the water in each of the cans after this time? temperature of water in temperature of water in temperature of water in X / C Y / C Z / C A 35 39 42 B 35 42 39 C 42 39 35 D 42 35 39

1 marks

Answer: A

This question in 0973/21 Oct/Nov 2020

33 Which example of thermal conduction involves energy transfer by electrons? A A person’s feet become warm when walking on hot sand. B Chocolate becomes warm if it is held in a hand. C One end of a metal spoon becomes hot when the other end is placed in hot water. D The outside of a plastic mug filled with hot water becomes hot.

1 marks

Answer: C

This question in 0973/21 May/June 2021

34 Which colour of outer clothing helps to keep the wearer cool on a hot, sunny day, and why is this clothing effective? colour of clothing why it is effective A black it is a good absorber of radiation from the Sun B black it is a poor absorber of radiation from the Sun C white it is a good absorber of radiation from the Sun D white it is a poor absorber of radiation from the Sun

1 marks

Answer: D

This question in 0973/21 May/June 2021

34 Four identical metal cans contain equal quantities of water at 80 C. The outer surfaces of two of the cans are dull and the outer surfaces of the other two cans are shiny. Lids are put on two of the cans, as shown. All the cans are allowed to cool. Which can cools the fastest? A B C D lid lid water water dull dull shiny shiny

1 marks

Answer: A

This question in 0973/22 May/June 2021

33 Solid metals transfer thermal energy by conduction. Which conduction process occurs only in metals? A Atoms move freely through the solid and carry energy. B Atoms vibrate about fixed positions and pass energy to neighbouring atoms. C Electrons move freely through the solid and carry energy. D Electrons vibrate about fixed positions and pass energy to neighbouring electrons.

1 marks

Answer: C

This question in 0973/22 May/June 2022

31 Which statement about thermal radiation is correct? A A dull surface is a good absorber and a good reflector of thermal radiation. B A dull surface is a poor absorber and a poor reflector of thermal radiation. C A shiny surface is a good absorber but a poor reflector of thermal radiation. D A shiny surface is a poor absorber but a good reflector of thermal radiation.

1 marks

Answer: D

This question in 0973/21 May/June 2023

33 Two methods of cooking are grilling under a red-hot heater and frying in a shallow metal pan. heater food shallow metal pan air food method 1: grilling method 2: frying How does thermal energy pass through the air to reach the food in method 1 and how does thermal energy pass through the bottom of the metal pan in method 2? method 1 method 2 A convection conduction B convection radiation C radiation conduction D radiation radiation

1 marks

Answer: C

This question in 0973/22 May/June 2023

33 A vacuum flask uses a vacuum between two shiny surfaces to keep a drink hot for a long time. glass walls with silvered surfaces hot drink vacuum How do the vacuum and the shiny surfaces help to keep the drink hot? vacuum shiny surfaces A prevents conduction and convection reduce conduction and radiation B prevents conduction and convection reduce radiation only C prevents radiation reduce conduction and convection D prevents radiation reduce convection only

1 marks

Answer: B

This question in 0973/21 Oct/Nov 2023

32 In a room, hot air above a heater rises and is replaced by cool air that falls. What is the name of this process, and how does the density of the hot air compare with the density of the cool air? process density of hot air A conduction greater than cool air B conduction less than cool air C convection greater than cool air D convection less than cool air

1 marks

Answer: D

This question in 0973/21 May/June 2024

32 Which region of the electromagnetic spectrum is often involved in heat transfer by radiation? A infrared B radio C ultraviolet D X-rays

1 marks

Answer: A

This question in 0973/22 May/June 2024

32 Some materials use atomic or molecular lattice vibrations and some materials use the movement of delocalised electrons for thermal conduction. Which row shows the correct materials? atomic or molecular movement of lattice vibrations delocalised electrons A metals only metals and plastics B plastics only metals and plastics C metals and plastics metals only D metals and plastics plastics only

1 marks

Answer: C

This question in 0973/21 May/June 2025

33 Which surface is the best absorber of thermal radiation? A dull black B dull white C shiny black D shiny white

1 marks

Answer: A

This question in 0973/21 May/June 2025

31 Which surface reflects the most thermal radiation? A a black, dull surface B a black, shiny surface C a white, dull surface D a white, shiny surface

1 marks

Answer: D

This question in 0973/22 May/June 2025