Thermal Energy Test

In some places, hot water from underground can shoot up into the air through a hole in the ground. When this happens, the ground surrounding the water increases in temperature. What happens to the molecules in the ground when the temperature of the ground increases?

• More heat molecules combine with the molecules in the ground.

• The energy of the molecules in the ground decreases.

• The energy of the molecules in the ground increases.

• The cold energy of the molecules in the ground decreases.

A space shuttle is covered with two layers of carbon. The two layers are the same size and have the same number of molecules. When the space shuttle is sitting on the ground, the layers do not touch, as shown in the diagram above. When the space shuttle takes off, the layers move so that they are touching. Use the information in the diagram to answer the question.

How does the temperature of the outer layer compare with the temperature of the inner layer before the layers touch? What will happen after the layers have been touching for a while?

• Before the layers touch, the outer layer is hotter than the inner layer. Once the layers are touching, the outer layer will transfer kinetic energy to the molecules in the cooler inner layer until both layers reach the same temperature, which will be in between their starting temperatures.

• Before the layers touch, the outer layer is hotter than the inner layer. Once the layers are touching, the cooler inner layer will gain kinetic energy until the molecules of both layers have an energy of 90, because hotter things increase the temperature of cooler things.

• Before the layers touch, the outer layer is cooler than the inner layer. Once the layers are touching, the inner layer will transfer kinetic energy to the molecules in the cooler outer layer until both layers reach the same temperature, which will be in between their starting temperatures.

• Before the layers touch, the layers are different temperatures. Once the layers are touching, kinetic energy and cold energy will transfer between the molecules in the two layers until both layers reach the same temperature, which will be in between their starting temperatures.

Conduction can only occur between two objects when –

• one object is less dense than the other.
• both objects are in physical contact with each other.
• one of the objects is made of a metal.
• both objects are exactly the same temperature.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

In the situation illustrated, how will heat energy move? Heat energy will be transferred from –

• the water to the hot plate by convection.
• the water to the hot plate by conduction.
• the hot plate to the water by convection.
• the hot plate to the water by conduction.

Radiation is a method of thermal energy transfer that moves -

• through empty space.
• when objects touch.
• only through solids.
• in the motion of fluids.

Tags

NGSS.HS-PS4-3

An example of a situation in which an egg is receiving thermal energy through convection -

• The egg is kept warm by its mother in the nest.
• An egg cracked on a hot sidewalk starts to cook.
• The egg is hard boiled in a pot of water.
• A metal pan on the stove fries the egg.

What two kinds of heat transfer are represented?

• stove→pot=radiation pot→egg=conduction
• stove→pot=conduction pot→egg=radiation
• stove→pot=convection pot→egg=conduction
• stove→pot=conduction pot→egg=convection

Which of the following is an example of conduction?

• Solar energy warming a room.
• Heat rising from the coils of a stove.
• Hot air drying a wet towel.
• Heat moving from a clothes iron to a shirt.

Tags

NGSS.MS-PS1-4

Which of following is a conductor?

• Wooden Stick
• Styrofoam Cooler
• Metal Pot
• Plastic Container

In the winter, some people heat their homes by burning logs in the fireplace.  How does the heat from the fire get to the other side of the room?

• it travels through the carpet by conduction
• it travels through the air by convection
• it travels through the carpet by radiation
• it travels with the smoke by condensation

Tags

NGSS.MS-PS1-4