yr 10 Energy Transfer Review

yr 10 Thermal Energy Transfer Review

Open Ended

Name the three ways that thermal energy can be transferred from one object to another?

Thermal energy transfer can happen by:

• conduction

• convection

• radiation

Multiple Choice

Which transfer type happens fastest in solids?

• conduction

• convection

• radiation

• none of them

Conduction requires particles to be close enough to pass their energy on through vibration, so not in liquids and gases!

Multiple Choice

Which is the best explanation for the poor thermal conductivity of gases?

• The particles are too small to carry much energy

• The particles are moving too fast to collide

• The particles do not stick together when they collide

• The particles do not collide very often

In gases, the particles are far apart and do not collide often enough to quickly pass on energy by conduction.

Multiple Choice

metals are excellent conductors of thermal energy because they contain...

• many protons

• free electrons

• strong forces

• thermal energy

Yes, free electrons make metals excellent conductors!

Open Ended

How is convection different from conduction?

Convection involves particles moving long distances and carrying the energy

In conduction, particles just vibrate

Multiple Choice

Convection is best described as...

• The movement of thermal energy carried by moving particles

• The transfer of thermal energy through intermolecular collisions

• The transfer of thermal energy through a solid substance

• The movement of particles from a hot substance to a cold one

Multiple Select

Convection can happen in...

(choose as many answers as you like)

• solids

• liquids

• gases

Multiple Choice

Convection cannot happen in solids because

• The particles are too heavy to move

• They contain free electrons

• The particles have a limit to how much energy they can hold

• The particles are not free to move

Multiple Choice

Thermal energy only travels from where there is a high temperature to where there is a low temperature.

• True

• False

• Sometimes true

Multiple Choice

Why is the freezer compartment at the top of a refrigerator?

• warm air sinks to the bottom

• conduction happens faster higher up

• it helps convection currents form

Radiation

Shiny suits reflect thermal energy rather than absorb it.

Multiple Choice

A black car will cool faster than a white one because

• black surfaces are good absorbers

• shiny surfaces are good absorbers

• black surfaces are good emitters

• black surfaces are good absorbers