Thermal Energy Transfer

Which best describes heat transfer by radiation?

• A slice of bacon frying in a pan.

• A pot on a stove boiling water.

• Cooking a hotdog in a microwave.

• A hot air balloon.

Answer explanation

Microwaves emit microwave radiation. Microwave radiation is part of the electromagnetic spectrum. Therefore when a Microwave cooks a hotdog it is using radiation to transfer energy to the molecules of the hotdog.

What enables fireman to enter buildings that are on fire and return from them safely?

• Convection cells keep fire away.

• The heat makes the building expand so there is no more room.

• Fireman wear heat resistant suits.

• They are really fast.

Answer explanation

The gear that a fireman wears must protect them from intense heat of fires. Insulators resist the flow of thermal energy from one place to another. Therefore a fireman must have gear that protects or insulates there body from the intense heat of the fire.

Which of the following best describes CONVECTION?

• When heat is transferred through waves.

• When heat is transferred through objects that are touching.

• The movement of gas or liquid in which warmer parts move up and the colder parts moves down.

Tags

NGSS.MS-PS1-4

What kind of heat transfer is occurring when the sun warms the sand?

• Conduction

• Convection

• Radiation

• All of them

Answer explanation

The sun warms the sand via radiation. The sand absorbs this energy and becomes hot.

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

Warm air rises and the cool air sinks demonstrates this type of heat transfer.

• Conduction

• Convection

• Radiation

Tags

NGSS.MS-ESS2-5

NGSS.MS-ESS2-6

Heat transfers from an area of ________ temperature to an area of _______ temperature.

• high to low

• low to high

• high to high

• low to low

Answer explanation

Thermal energy is transferred between substances of different temperatures. This energy moves from areas of high concentration (higher temperatures) to areas of low energy (lower temperatures) until they reach thermal equilibrium.

Tags

NGSS.MS-PS3-3

NGSS.MS-PS3-4

Walking on a warm sand with your bare feet shows this type of heat transfer.

• conduction

• convection

• radiation

Answer explanation

Conduction occurs when two objects or substances touch. When objects touch thermal energy transfer via conduction occurs.

Tags

NGSS.MS-PS1-4

Ironing a shirt is an example of:

• condensation

• evaporation

• conduction

• convection

Answer explanation

Conduction occurs when objects touch. Therefore when the iron touches the shirt conduction occurs. The iron is transferring thermal energy by TOUCHING the shirt.

Tags

NGSS.MS-PS1-4

You and your friends gathered around a campfire to keep warm. How heat is being transferred?

• conduction

• convection

• radiation

Answer explanation

What we see as fire is light. Light is electromagnetic radiation. The energy from the fire is transferred to our bodies via radiation or light energy.

This is the transfer of thermal energy through "space".

• conduction

• radiation

• convection

• spaceship

Answer explanation

The sun emits light or electromagnetic radiation that transfers energy from the sun to Earth.

Tags

NGSS.MS-PS1-4

NGSS.MS-PS3-3