Ch. 5 Thermal Energy Review

What is thermal energy?

• The energy of moving objects

• Energy stored in batteries

• The sum of kinetic and potential energy of all the particles in an object.

• The energy of light

Answer explanation

Thermal energy is the total energy of all particles in an object, combining their kinetic and potential energy. This makes the correct choice the sum of kinetic and potential energy of all the particles in an object.

Tags

NGSS.MS-PS1-4

When you heat something up, what happens to the particles inside it?

• The particles stop moving

• The particles move faster

• The particles disappear

• The particles get bigger

Answer explanation

When you heat something, the energy increases, causing the particles to move faster. This is why the correct answer is that the particles move faster, as they gain kinetic energy with heat.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which of these is a good conductor of heat?

• Plastic

• Metal

• Wood

• Rubber

Answer explanation

Metal is a good conductor of heat due to its free electrons that facilitate the transfer of thermal energy. In contrast, plastic, wood, and rubber are insulators and do not conduct heat well.

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

Which of these materials will keep your hands warm if you touch something cold?

• Wool gloves

• Metal fork

• Plastic spoon

• Glass cup

Answer explanation

Wool gloves are designed to provide insulation and retain heat, keeping your hands warm when touching cold objects. In contrast, metal, plastic, and glass do not offer insulation and can conduct cold, making them unsuitable for warmth.

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

What happens to the temperature of a substance when its particles move faster?

• The temperature decreases

• The temperature stays the same

• The temperature increases

• The temperature disappears

Answer explanation

When particles of a substance move faster, they have more kinetic energy, which results in an increase in temperature. Therefore, the correct answer is that the temperature increases.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-4

Which of the following is an example of thermal energy transfer by conduction?

• Sunlight warming your face

• A metal spoon getting hot in a pot of soup

• Warm air rising to the ceiling

• A fan blowing air across a room

Answer explanation

Conduction is the transfer of thermal energy through direct contact. A metal spoon getting hot in a pot of soup is a clear example, as heat moves from the hot soup to the cooler spoon through direct contact.

Tags

NGSS.MS-PS1-4

What is the main method of heat transfer in liquids and gases?

• Conduction

• Radiation

• Convection

• Insulation

Answer explanation

The main method of heat transfer in liquids and gases is convection. This process involves the movement of fluid, which carries heat with it, unlike conduction, which occurs in solids, and radiation, which does not require a medium.

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

Which of the following is an insulator?

• Copper wire

• Aluminum foil

• Wool blanket

• Steel rod

Answer explanation

A wool blanket is an insulator, meaning it resists the flow of electricity and heat. In contrast, copper wire, aluminum foil, and steel rod are conductors, allowing electricity to pass through them easily.

Tags

NGSS.MS-PS2-3

What is the process called when heat is transferred through empty space?

• Conduction

• Convection

• Radiation

• Insulation

Answer explanation

The process of heat transfer through empty space is called radiation. Unlike conduction and convection, which require a medium, radiation can occur in a vacuum, allowing heat from the sun to reach the Earth.

Which of the following is an example of radiation?

• Boiling water in a pot

• Heat from a campfire warming your hands

• Ice melting in your hand

• A hot pan on a stove

Answer explanation

Radiation is the transfer of heat through electromagnetic waves. The heat from a campfire warming your hands is an example of radiation, as it travels through the air without needing direct contact, unlike the other options.