Activity 3.5 Heat Transfer Pre-Assessment

You take a cold can of soda off of a countertop. The countertop underneath the can feels colder than the rest of the counter. Which of the following explains this occurrence?

• The cold has been transferred from the soda to the counter.

• There is no heat energy left in the counter beneath the can.

• Some heat has been transferred from the counter to the soda.

• The heat beneath the can moves away into other parts of the countertop.

After cooking an egg in boiling water, you cool the egg by putting it into a bowl of cold water. Which of the following explains the egg’s cooling process?

• Temperature is transferred from the egg to the water.

• Cold moves from the water into the egg.

• Energy is transferred from the water to the egg.

• Energy is transferred from the egg to the water.

Why do we wear sweaters in cold weather?

• To keep cold out.

• To generate heat.

• To reduce heat loss.

• All of the above.

For each question, circle the answer that you know or believe to be correct. Be sure to read all of the choices before selecting the best answer. 4. Amy wraps her dolls in blankets but can’t understand why they don’t warm up. Why don’t they warm up?

• The blankets she uses are probably poor insulators.

• The blankets she uses are probably poor conductors.

• The dolls are made of materials which don’t hold heat well.

• None of the above.

As water in a freezer turns into ice,

• the water absorbs energy from the air in the freezer.

• the water absorbs the coldness from the air in the freezer.

• the freezer air absorbs heat from the water.

• the water neither absorbs nor releases energy

On a warm sunny day, you will feel cooler wearing light colored clothes because they

• reflect more radiated heat energy.

• prevent sweating.

• are not as heavy as dark clothes.

• let more air in.

If you put a metal spoon and a wooden spoon into a pot of boiling water, one will become too hot to touch. Why?

• Metals conduct heat better than wood.

• Wood conducts heat better than metals.

• Metals pull in heat because heat is attracted to metals.

• Wood isn’t as strong as metals.

On a hot day, the upstairs rooms in a house are usually hotter than the downstairs rooms. Why?

• Cool air is less dense than hot air.

• Warm air rises and cool air sinks.

• The roof insulation warms the air.

• Heat rises.

You have a can of soda in your lunchbox that you want to keep cold. Which material will work best to keep it cold?

• Aluminum foil wrapped around the soda because metals transfer heat energy easily.

• A paper towel wrapped around the soda because paper soaks up the moisture.

• Wax paper wrapped around the soda because wax paper traps the moisture.

• Your wool sweater wrapped around the soda because wool traps air.

When you hold a metal coat hanger in a camp fire to roast a marshmallow, the coat hanger might become too hot to hold. Why might the coat hanger get too hot?

• The heat radiates along the coat hanger.

• The heat builds up near the flame until it can’t hold it anymore and then moves along the coat hanger.

• Metal atoms vibrate with more energy when they get hot, and they collide with atoms near them, which causes the neighboring atoms to vibrate.

• Since metals melt in fire, they react strongly to fire and get hot easily.