Name:
Date:
Ch. 5 Thermal Energy Review
Period:
1. Define the following:
Heat- transfer of energy between objects, due to a difference in temperature.
Temperature- the measure of the average kinetic energy of an object
Thermal Energy- the total amount of kinetic and potential energy in an object TE= KE + PE
Conduction- transfer of thermal energy by collisions between particles that make up matter.
Convection- transfer of thermal energy in a fluid or gas by the movement of warmer fluid/gas from one place to another
Radiation-transfer of energy by electromagnetic waves
Specific Heat- amount of heat needed to raise the temperature of an object 1 kg of material by 1 degree Celsius
2. Heat is thermal energy moving from a ________ object to a ________ object
a) warmer; cooler
b) cooler; warmer
c) stationary; moving
d) slower; faster
3. List three ways heat can transfer: Conduction, Convection, Radiation
4. Energy from the sun is __Radiant Energy____________.
5. Explain specific heat: amount of heat needed to raise temperature of 1 kg of material by 1 ᵒC
6. Which of the following are good conductors of heat: copper, plastic, glass, aluminum
7. Thermal energy _______________ as temperature increases.
a)increases b) decreases c) remains constant d)contracts
8. Which of the following do NOT require the presence of matter particles?
a)conduction b) convection c) radiation d) condensation
9. Explain how heat is transferred in convection:
heat is transferred by the movement of currents within a fluid or gas
10. Draw and identify where convection, conduction, and radiation occur in the picture below:
11. Identify the SI unit used for temperature: Kelvin (K)
12. Which law of thermodynamics states that it’s impossible for heat to flow from cool objects to warmer objects?
2nd Law of Thermodynamics
13. A material that reduces the flow of heat is a(n) __insulator____________________.
14. Explain why solids and liquids are better conductors of heat than gases.
15. Heat is a form of energy, so it is measured in _Joules______________.
16. Explain why the specific heat of water makes it a useful coolant.
Water has high specific heat so it can absorb heat without large change in temperature.
17. The sum of ______ and _______ of all the particles in an object is the thermal energy of the object.
a)speed; direction b) specific heat; temperature c) potential energy; kinetic energy d) mass; volume
18. Your grandma needs to put on oven mitts when taking a hot pan out of the oven. Determine which transfer of
thermal energy she is being careful to avoid. Conduction- hands on hot pan
19. Explain why the following will affect the thermal energy of an object:
a) increasing the temperature of an object increases its thermal energy- kinetic energy increases
b) increasing the mass of an object increases its thermal energy- more particles= more thermal energy
c) changing the state of matter of an object from a liquid to a solid- molecules are more spread out
20. Solar heating systems convert __radiant______ energy from the Sun to __thermal_________ energy.
21. Explain how a jacket with air pockets acts as a good insulator during winter. Air slows the flow of body heat to the
colder outside air
22. Explain how kinetic energy is transferred during conduction. Particles collide through matter by direct contact
23. _Thermodynamics__________ is the study of the relationships between heat, work, and thermal energy.
24. The _First Law _________ of thermodynamics states that if the mechanical energy of a system is constant, then the
increase in thermal energy of that system equals the work done on that system plus the thermal energy transferred into
that system.
25. The change in volume of a material due to temperature change is due to __thermal expansion_________.
Give an example: thermometer
Explain why this occurs: the liquid expands as the kinetic energy increases