Physics Term 4 Heat

Question 1

Explain the difference between heat and temperature.

Answer 1

Heat is the transfer for thermal energy from a body with a hotter temperature to one with a cooler temperature (measured in joules)

Temperature is a measure of the average kinetic energy of particles (measured in C, F and Kelvin (K))

Question 2

Recall the meaning of conduction

Answer 2

Conduction: heat transfer through direct contact between particles in a solid substance.

Question 3

Recall the meaning of convection

Answer 3

the transfer of heat through the movement of fluids (liquids and gases).

Question 4

Recall the meaning of radiation

Answer 4

the transfer of heat in the form of electromagnetic waves without the need for a medium.

Question 5

Outline how heat is transferred (in terms of conduction, convection and radiation)

Answer 5

Conduction
direct contact between particles in a solid.

Convection
the movement of fluids, where warm fluid rises and cooler fluid sinks.

Radiation
electromagnetic waves, traveling without a medium.

Question 6

Describe how the rate of transfer can be changed.

Answer 6

Conduction:
Increase temperature difference.
Use materials with higher conductivity.

Convection:
Increase fluid movement.
Change fluid temperature or density.

Radiation:
Increase temperature.
Use larger or darker surfaces.

Question 7

Recall the meanings of insulator and conductor (and provide examples for each).

Answer 7

Conductors: materials that are good at transferring heat energy (metal, copper)

Insulators are materials that are poor at transferring heat energy. (plastic, rubber, glass)

Question 8

Recognize that materials have different levels of insulation/conduction of heat.

Answer 8

Different materials have varying abilities to conduct heat.