7th Heat and Temperature [Formative Assessments -01]

1. Radiation
(a) does not require any medium
(b) is the process of transfer of heat in liquids
(c) is the process of transfer of heat in which heat traveles in one direction.
(d) Occurs in solids.

2. A Thermos flask prevents loss or gain of heat by
a. conductions only
b. convections only
c. radiation only
d. all the above

3. Handles of cooking utensils should be made of material that
a. conducts heat well
b. does not conduct heat
c. radiate heat well
d. does not radiate heat

4. Sea breeze and land breeze
a. are caused by currents set up in air due to conduction
b. are caused by currents set up in air due to convection
c. are caused by currents set up in air due to radiation
d. have no relation to conduction, convection and radiation

5. Which of the following is the best heat insulator
a. air
b. steel
c. copper
d. iron

6. Heat from the sun reaches us by the process of
a. conduction
b. convection
c. radiation
d. all the above

7. In liquids heat is transferred
a. only by convection
b. only by radiation
c. mainly by conduction and convection
d. none of these

8. Stainless steel pans are provided with copper bottom because
a. copper is easier to clean than stainless steel
b. such pans are colourful
c. copper bottom makes the pan more durable
d. copper is better conductor of heat than stainless steel

9. A polished silvery surface is
a. good absorber of heat
b. good reflector of heat
c. poor reflector of heat
d. None of these

10. Land breeze blows in coastal regions during
a. day
b. summer
c. winter
d. night

11. A wooden spoon is dipped in a cup of icecream. Its other end

a. does not become cold
b. becomes cold by the process of radiation
c. becomes cold by the process of convection
d. becomes cold by the process of conduction

12. Dark coloured clothes are preferred during
(a) summer
(b) sand storm
(c) winter
(d) none of these

13. A black body with rough surface is a
a. good reflector and poor absorber of heat
b. good absorber and good radiator of heat
c. good absorber and poor radiator of heat
d. good reflector and poor radiator of heat

14. Range of laboratory thermometer is generally from
a. -10 F to 110 F
b. 10 C to 110 C
c. 10 C to -110 C
d. -10 C to 110 C

15. Normal temperature of human body is
(a) 37 F
(b) 37 C
(c) 39 C (
d) 39F
16. Which of the following is a good conductor of heat
(a) Wool
(b) Water
(c) Wood
(d) Silver

17. Device used for measuring temperature
(a) Barometer
(b) Odometer
(c) Thermometer
(d) Speedometer

18. Transmission of heat energy with actual movement of particles
(a) Conduction
(b) Convection
(c) Radiation
(d) None of these.

19. When two bodies are kept in contact heat flows from
a. a body at higher temperature to the body at lower temperature
b. a body at lower temperature to the body at higher temperature
c. no flow of heat
d. all of the above

20. A cold steel spoon dipped in a cup of hot milk. It transfers heat to the other end by the process of
(a) radiation
(b) convection
(c) conduction
(d) none of these

1. a 2. d 3. b 4. b 5. a 6. c 7. a 8. d 9. b 10. d
11. a 12. c 13. b 14. d 15. b 16. d 17. c 18. b 19. a 20. c

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