Conduction and Convection

When air is heated, its volume ____________.

• increases

• remains the same

• decreases

The diagram shows some rice being boiled in a pan. What is the main methods by which thermal energy is transferred (i) through the metal pan and

(ii) through the water?

• (i) conduction (ii) conduction

• (i) convection (ii) convection

• (i) conduction (ii) convection

• (i) convection (ii) conduction

Convection can take place in ____________.

• solids only.

• liquids only.

• liquids and gases only.

• solids, liquids and gases.

Which of the following correctly shows the direction of convection currents in water?

• A

• B

• C

• D

In convection, COOL air

• Rises

• Sinks

In convection, WARM air

• Rises

• Sinks

Heat transfers from an area of ____temperature to an area of ___ temperature.

• high to low

• low to high

• high to high

• It can travel high to low and low to high.

If differences in air pressure produce winds, what can you conclude about temperature and air pressure based on the figure?

• As warm air rises, it creates an area of lower pressure, and cooler air flows in as wind

• Warm air is denser than cold air is, creating an area of high pressure the produces wind.

• Winds flow from areas of low pressure to areas high pressure when temperature is warmer

• Air pressure decreases at night because temperature is lower, producing land and sea breezes

Which statement is true?

• The quicker a molecule moves, the colder it is.

• The quicker a molecule moves, the warmer it is

• The slower a molecule moves, the warmer it is.

• The movement on molecule do not affect its temperature.

Which direction is heat flowing in the picture?

• from the ice to the hand

• heat is not being transferred

• from the hand to the ice