Heat Transfer

Define heat.

• Opposite of cold

• Property of having a temperature above 30^oC

• Sensation or feeling of being warm

• Thermal energy that is transferred from one substance to another

When you cook pancakes in a hot pan, determine which direction heat moves.

• Between the pan and the pancakes, in both directions

• From the pancakes to the pan

• From the pan to the pancakes

• There is no movement of heat

Select two options that best complete the sentence.

Two dinner plates are identical. One is placed in a hot oven and the other is placed in a cold fridge. After ten minutes, the plate in the oven has:

• more thermal energy

• less thermal energy

• particles with more kinetic energy

• particles with less kinetic energy

Identify why your hand feels cold as an ice cube melts on it.

• Cold energy is transferred from the ice to your hand

• Thermal energy can't transfer between your hand and ice

• Thermal energy is transferred from your hand to the ice

• Thermal energy is transferred from the ice to your hand

Explain why water vapour, a gas, has more thermal energy than an equal amount of ice? Use the following terms: particles, kinetic energy and thermal energy.

Define conduction.

The transfer of heat:

• by currents as hot substances rise and cold substances fall

• across empty space, such as from the Sun to Earth

• between substances in direct contact with one another

• from cooler objects to hotter ones

Recall what type of energy is passed between particles during conduction.

• Light

• Kinetic

• Chemical

• Speed

A cold metal spoon is placed in a bowl of hot soup. Identify which of the following statements is correct.

• Thermal energy is transferred from the spoon to the soup

• The particles in the spoon are moving faster than the particles in the soup

• Thermal energy is transferred from the soup to the spoon

• Thermal energy is not transferred between the soup and the spoon

Select the option that best completes the following sentence.

Insulators:

• allow heat to easily flow through them

• are usually made of metal

• tend to feel very cold or hot when you touch them

• do not allow heat to easily flow through them

You step out of the shower onto the bathroom mat. You then walk along the tiles. The tiles feel much colder than the bathroom mat. Explain why.