HCI Worksheet 11 Kinetic Model Transfer of Thermal Energy Temperature (IP)

Hwa Chong Institution Sec 3 Physics 1 Name: ____________________________________________ Class: __________ Date: ____________ Sec 3 Physics Worksheet 11: Kinetic Model of Matter, Transfer of Thermal Energy, Temperature & Thermometry SECTION A: MULTIPLE CHOICE QUESTIONS 1. Diagram 1 shows smoke particles in a transparent box observed using a microscope. Small points of light are seen to move around, as shown in diagram 2. What does this experiment demonstrate about air molecules? A They are in continuous random motion. B They can be seen through a microscope. C They move more quickly when they are heated. D They move because of collisions with smoke particles. E They give out light when they collide with smoke particles. ( ) 2. The diagram shows a model to demonstrate the behaviour of gas molecules. When the piston is vibrated more rapidly, the wooden disc is forced further up the tube. Weights have to be placed on the disc to return it to its original position. The model represents what happens to a gas when it is A cooled, then compressed. B cooled, then heated. C heated, then compressed. D heated, then cooled. E expanded then cooled. ( )

Hwa Chong Institution Sec 3 Physics 2 3. The volume of a constant mass of gas in a cylinder is reduced at a constant temperature. The pressure exerted by the molecules of the gas increases because A the gas molecules speed up. B the density of the gas increases. C the gas molecules collide with each other more often. D the gas molecules strike the cylinder walls more often. E there is a smaller area of the cylinder in contact with the gas. ( ) 4. A student observes the Brownian motion of smoke particles in the air with a microscope. She sees moving points of light. These points of light come from A air particles are only moving randomly. B air particles are only vibrating. C smoke particles are only moving randomly. D smoke particles are only vibrating. E both smoke and air particles moving randomly. ( ) 5. Some gas is heated in a sealed container. Which of the following does not increase? A The force due to the collisions between the gas molecules and the container walls. B The number of collisions per second by the gas molecules on the container walls. C The average kinetic energy of gas molecules. D The average speed of the gas molecules. E The average distance between gas molecules. ( ) 6. Some gas trapped in a cylinder is compressed at con stant temperature by a piston. Which of the following will not change? A Density B Mass C Molecular spacing D Pressure E Volume ( ) 7. When the temperature of a gas rises at a constant volume, its molecules A move closer together. B move with greater average speed. C collide with one another less often. D exert smaller forces on one another. E expand. ( )

Hwa Chong Institution Sec 3 Physics 3 8. When a solid is heated, which of the following changes occurs? A The density increases. B The latent heat increases. C The melting point increases. D The molecules vibrate more rapidly. E The number of molecules increases. ( ) 9. Which states of matter are very difficult to compress? A Gases only B Gases and liquids only C Gases, liquids and solids D Liquids and solids only E Solids only ( ) 10. A fixed mass of gas is heated while kept at a constant volume. How do the properties of the molecules of the gas change? Average speed Frequency of collision with walls Average distance apart A Increases Increases Unchanged B Increases Increases Decreases C Increases Unchanged Unchanged D Unchanged Increases Increases E Unchanged Unchanged Decreases ( ) 11. Why does the pressure of a fixed mass of gas increase when it is heated at constant volume? A More molecules are created by heating. B The average mass of the molecules increases. C The average speed of the molecules increases. D The molecular collisions become more elastic. ( ) 12. The Brownian motion of smoke particles is caused by A collisions between air molecules. B collisions between smoke particles. C collisions between smoke particles and air molecules. D convection currents in the air. ( ) 13. If heat is removed from an object, its temperature will normally A fall. C rise. B fall, then rise. D rise then fall. ( )

Hwa Chong Institution Sec 3 Physics 4 14. An unlit match is held near to a scorching bunsen flame. The match does not get hot enough to light because A the flame is not hot enough. B air is a bad conductor of heat. C the match head reflects radiation. D the flame does not radiate any heat sideways. ( ) 15. How may heat be transferred through a vacuum? A by convection only B by radiation only C by conduction only D by conduction and convection only ( ) 16. Boiling water and ice can exist at the same time in a test tube. What does this experiment show? A Ice conducts heat well. B Metal gauze conducts heat poorly. C Water conducts heat well. D Water conducts heat poorly. ( ) 17. A copper plate is heated to 100 C . It cools by emitting A electrons. B  − radiation C infra-red radiation. D ultraviolet radiation. ( )

Hwa Chong Institution Sec 3 Physics 5 18. By what process does a beaker of hot water lose energy? A conduction, convection and evaporation only B conduction, convection and radiation only C conduction, convection, evaporation and radiation D evaporation and radiation only ( ) 19. Which types of surface are the best absorbers and the best emitters of infra-red radiation? Best absorber Best emitter A black and dull black and dull B black and shiny white and dull C white and dull black and shiny D white and shiny white and shiny ( ) 20. When you stand in bare feet with one foot on a stone floor and the other on a carpet, the stone floor feels colder than the carpet. The most likely explanation is that A air is unable to circulate through the carpet fibres. B more energy flows from the carpet to your foot than from the stone floor to your foot. C more energy flows from your foot to the stone floor than to the carpet. D the stone floor is at a lower temperature than the carpet. ( ) 21. The diagram shows the positions of the mercury threads in a thermometer. What is the distance between each 1 C mark on the thermometer? A 0.22 cm B 0.24 cm C 2.0 cm D 2.2 cm ( )

Hwa Chong Institution Sec 3 Physics 6 22. The diagram shows a mercury -in-glass thermometer. The distance between the −10 C and the 110 C markings is 25 cm. At which temperature is the end of the mercury thread 15 cm from the -10oC mark? A 50 C B 60 C C 62 C D 72 C ( ) 23. The lengths of mercury thread in the uniform tube above the bulb of a mercury thermometer are: 20 mm when the bulb is in melting ice; 170 mm when the bulb is in the steam above boiling water; 50 mm when the bulb is in a liquid X. What is the temperature of liquid X? A 20 C B 25 C C 30 C D 33.3 C ( ) 24. A thermometer reads 1 C in pure melting ice and 101 C in the steam above boiling water. It is used to measure the temperature of the water before and after it is heated. What is the error when the temperature rise is calculated? A 2 C too low B 1 C too low C zero D 1 C too high ( ) 25. How can the sensitivity of a liquid-in-gl