Heat And Thermodynamics - Heat Transfer Check For Understanding Quiz

1. 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.

Metals conduct heat better than wood because they have a higher thermal conductivity. This means that they are able to transfer heat more efficiently from the boiling water to the spoon. Wood, on the other hand, has a lower thermal conductivity, so it is not as effective at conducting heat. As a result, the metal spoon will become hotter than the wooden spoon when placed in the pot of boiling water.

Explanation

Metals conduct heat better than wood because they have a higher thermal conductivity. This means that they are able to transfer heat more efficiently from the boiling water to the spoon. Wood, on the other hand, has a lower thermal conductivity, so it is not as effective at conducting heat. As a result, the metal spoon will become hotter than the wooden spoon when placed in the pot of boiling water.

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

Reflect more radiation.

Prevent sweating.

Are not as heavy as dark clothes.

Let more air in.

Light-colored clothes reflect more radiation, including sunlight, compared to dark-colored clothes. When radiation, such as sunlight, hits an object, it can be absorbed or reflected. Dark-colored clothes absorb more radiation, which leads to an increase in heat. On the other hand, light-colored clothes reflect more radiation, reducing the amount of heat absorbed by the body and making the person feel cooler.

Explanation

Light-colored clothes reflect more radiation, including sunlight, compared to dark-colored clothes. When radiation, such as sunlight, hits an object, it can be absorbed or reflected. Dark-colored clothes absorb more radiation, which leads to an increase in heat. On the other hand, light-colored clothes reflect more radiation, reducing the amount of heat absorbed by the body and making the person feel cooler.

3. When placed in direct sunlight, which object will absorb the most radiation?

A white sweater

A snowball

Some aluminum foil

A black sweater

Dark colors absorb, light colors reflect.

Explanation

Dark colors absorb, light colors reflect.

4. On a sunny 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 upstairs rooms are closer to the sun.

Heat rises.

Warm air rises and cool air sinks because of the principle of convection. When air is heated, it expands and becomes less dense, causing it to rise. As it rises, it creates a vacuum that pulls in cooler air from below, which then gets heated and rises as well. This creates a continuous cycle of warm air rising and cool air sinking. Therefore, on a sunny day, the upstairs rooms in a house are usually hotter than the downstairs rooms because warm air naturally rises upwards.

Explanation

Warm air rises and cool air sinks because of the principle of convection. When air is heated, it expands and becomes less dense, causing it to rise. As it rises, it creates a vacuum that pulls in cooler air from below, which then gets heated and rises as well. This creates a continuous cycle of warm air rising and cool air sinking. Therefore, on a sunny day, the upstairs rooms in a house are usually hotter than the downstairs rooms because warm air naturally rises upwards.

5. 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 that don’t hold heat well.

None of the above.

The dolls are made of materials that don't hold heat well. This means that they are not able to retain or trap heat within them. Therefore, even if Amy wraps them in blankets, the dolls will not warm up because the materials they are made of do not have the ability to hold onto heat.

Explanation

The dolls are made of materials that don't hold heat well. This means that they are not able to retain or trap heat within them. Therefore, even if Amy wraps them in blankets, the dolls will not warm up because the materials they are made of do not have the ability to hold onto heat.

6. An aluminum plate and a plastic plate have been in the freezer all night long. When you remove them the next morning,

The plates have the same temperature.

The plastic plate has a higher temperature.

The plastic plate has a lower temperature.

The aluminum plate has a lower temperature.

0th Law of Thermodynamics

Explanation

0th Law of Thermodynamics

7. When you hold a metal coat hanger in a camp fire to roast a marshmallow, the coat hanger might get 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

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

When the metal coat hanger is exposed to the campfire, the heat causes the metal atoms to vibrate with more energy. These vibrating atoms then collide with neighboring atoms, transferring the energy and causing them to vibrate as well. This process continues, resulting in the heat spreading along the coat hanger. Eventually, the coat hanger becomes too hot to hold as the heat continues to transfer from atom to atom.

Explanation

When the metal coat hanger is exposed to the campfire, the heat causes the metal atoms to vibrate with more energy. These vibrating atoms then collide with neighboring atoms, transferring the energy and causing them to vibrate as well. This process continues, resulting in the heat spreading along the coat hanger. Eventually, the coat hanger becomes too hot to hold as the heat continues to transfer from atom to atom.

8. 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.

2nd Law -- heat goes from hot to cold.

Explanation

2nd Law -- heat goes from hot to cold.

9. You pick up a can of soda off of the countertop. The countertop underneath the can feels colder than the rest of the counter. Which explanation do you think is the best?

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.

2nd Law of Thermodynamics -- heat transfer is from hot to cold only -- messiness spreads.

Explanation

2nd Law of Thermodynamics -- heat transfer is from hot to cold only -- messiness spreads.

10. 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.

When water in a freezer turns into ice, the process involves the removal of heat energy from the water. As a result, the water loses heat to the surrounding air in the freezer. Therefore, the freezer air absorbs heat from the water.

Explanation

When water in a freezer turns into ice, the process involves the removal of heat energy from the water. As a result, the water loses heat to the surrounding air in the freezer. Therefore, the freezer air absorbs heat from the water.

11. Why do we wear sweaters in cold weather?

To keep cold out.

To generate heat.

To reduce heat loss.

All of the above.

We wear sweaters in cold weather to reduce heat loss. Sweaters act as insulating layers that trap our body heat and prevent it from escaping into the surrounding cold air. By reducing heat loss, sweaters help to keep us warm and maintain our body temperature in cold weather conditions. Wearing sweaters also helps to conserve energy as our bodies don't have to work as hard to generate heat.

Explanation

We wear sweaters in cold weather to reduce heat loss. Sweaters act as insulating layers that trap our body heat and prevent it from escaping into the surrounding cold air. By reducing heat loss, sweaters help to keep us warm and maintain our body temperature in cold weather conditions. Wearing sweaters also helps to conserve energy as our bodies don't have to work as hard to generate heat.

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

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.

Wool is a good insulator because it has a lot of air pockets within its fibers. When the soda is wrapped in a wool sweater, the air trapped within the wool acts as a barrier against heat transfer. This helps to keep the soda cold by preventing the outside temperature from reaching the soda and transferring heat to it.

Explanation

Wool is a good insulator because it has a lot of air pockets within its fibers. When the soda is wrapped in a wool sweater, the air trapped within the wool acts as a barrier against heat transfer. This helps to keep the soda cold by preventing the outside temperature from reaching the soda and transferring heat to it.