Heat & Light Test Revision 1

Question 1

Heat transfer methods

Answer 1

Conduction, convection, radiation

Question 2

Conduction

Answer 2

• Heat through direct contact
• When things at 2 different temps come into contact, the hotter region transfers some of its thermal energy to teh colder region
• This occurs due to collision of particles in hotter region which transfers energy to particles in colder region

Question 3

Convection

Answer 3

• Heat transfer that occurs in fluids (liquids or gases) due to movement of fluid itself
• When a fluid is heated, its particles gain energy and move faster, causing them to spread out and become less dense
• The less dense, warmer fluid rises
• The denser, cooler liquid sinks
• This creates a circular motion called convection currents

Question 4

Radiation

Answer 4

• The transfer of heat energy through electromagnetic waves
• Radiation does not require a medium to transfer heat
• Heat energy can be emitted in the form of electromagnetic waves, and can travel through empty space

Question 5

Heat vs temperature

Answer 5

Heat
- form of energy transfer
- transfer between 2 objects or within a substance
- describes transfer of energy
- measures in Joules (J)

Temperature
- referees to measure of average kinetic energy of particles in substance/object
- determines how hot or cold object is
- measure in ºC

Question 6

Longitudinal wave

Answer 6

Type of wave in which medium’s vibration is parallel to direction of the wave, and medium displacement is in the same direction as that wave movement.

Question 7

Transverse wave

Answer 7

A wave in which the vibrating element moves in a direction that is perpendicular (intersect at 90º) to the direction of advance of the wave

Question 8

Wave frequency

Answer 8

Number of wave crests passing Point A each second

Question 9

Wave period

Answer 9

The time required for the wave crests at Point A to reach Point B