Welcome to your Thermal Properties and Processes - Expansivity, Heat Transfer(Senior Class Physics Study by Topics) NAME EMAIL PHONE NUMBER 1. A block of copper weighs 3.0 kg. Copper has a specific heat capacity of 390 J kg-1K-1. It is cooled in the freezer so that the temperature drops from 25.0oC to 0.0oC. What is the total energy lost by the block of copper? 29250 J 32950 J 22950 J 23400 J 2. Calorie is defined as the amount of heat required to raise the temperature of 1g of water by 1°C and it is defined under which of the following conditions? From 3.5°C to 4.5°C at 76mm of Hg From 13.5°C to 14.5°C at 76mm of Hg From 14.5°C to 15.5°C at 760mm of Hg From 98.5°C to 99.5°C at 760mm of Hg 3. Which of the following is an effective coolant? Oil Mecury Acids Water 4. Internal energy is The sum of molecular kinetic energy and molecular potential energy of a body The average molecular kinetic energy and average molecular potential energy of a body Thermal energy that a body possesses The sum of kinetic energy and potential energy of a body 5. The outer ends of two bars A and B are at 100°C and 50° respectively. Calculate the temperature at the welded joint if they have the same cross-section and the same length and their thermal conductivities are in the ratio of A:B = 7:5. 80.548°C 58.147°C 79.166°C 20.157°C 6. Why is the roof of buildings painted white Because it is cheaper Because it absorbs radiation Because it conducts heat Because it reflects radiations 7. When potassium is added to water, it is seen that the lower region becomes warm first and becomes less dense. It then moves up and the more dense cold water comes down and the process goes on. What is the process taking place? Conduction Convection Radiation Purification 8. Temperature is a microscopic concept. True False 9. Which term is used to define the temperature at which a substance changes its status from solid to liquid? Freezing point Condensation point Boiling point Melting point 10. When one end of the rod is heated, the molecules at the hot end vibrate with higher amplitude and transmit the heat from one particle to the adjacent particle and so on. What is the process? Conduction Radiation Convection Transmittance 11. If the sun were to increase in temperature from T to 2T and its radius from R to 2R, then the ratio of the radiant energy received on earth to what it was previously, will be _______ 16 32 4 64 12. The response of a material due to the function of heat is known as __________ Mechanical property Chemical property Thermal property Electrical property 13. On a hilly region, water boils at 95°C. What is the temperature expressed in Fahrenheit? 100°F 20.3°F 150°F 203°F 14. A composite rod made of copper (1.8×10(-5) K(-1)) and steel (α=1.2×10(-5) K(-1)) is heated. Then _____ It bends with steel on concave side Data is insufficient It bends with copper on concave side It does not expand 15. Temperatures of two stars are in ratio 3:2. If wavelength of maximum intensity of first body is 4000 Å, what is corresponding wavelength of second body? 6000 Å 9000 Å 2000 Å 8000 Å 16. Compared to burn due to air at 100°C, a burn due to steam at 100°C is _______ More dangerous Equally dangerous Less dangerous Not dangerous 17. A piece of blue glass heated to a high temperature and a piece of red glass at room temperature, are taken inside a room that is dimly lit, then ___________ The blue piece will look blue and red will look as usual Blue shines like brighter red compared to the red pieces Both the pieces will look equally red Red looks brighter and blue looks ordinary blue 18. What is the SI unit of specific heat capacity? JK/kg J/(kgK) Jkg/K J/kg 19. The energy due to which the molecules held at a fixed position vibrate, this energy is termed as internal energy chemical energy external energy physical energy 20. The thermometer bulb should have ______ High heat capacity Small heat capacity No heat capacity Varying heat capacity 21. When the first law of thermodynamics, Q = ΔU + W, is applied to an ideal gas that is taken through an isothermal process, Q = 0 ΔU = 0 W = 0 None of the above 22. What happens when you heat china having some dark paintings engraved on it at 1000°C and then examine it in a dark room immediately? The china dish will develop patterns The china dish doesn’t glow The dark painting will appear much brighter The whole china dish will be bright 23. The melting point of Iron (Fe) is _________ 1538°C 660°C 1084°C 419°C 24. In an isochoric process, the internal energy of a system decreases by 50 J. What is the heat exchange? -50 J None of the above 50 J Zero 25. The ability of a body to withstand sudden and severe temperature changes is known as________ Thermal resistance Thermal shock resistance Deployment Thermal transmittance 1 out of 25 Time is Up! Time's up