Heat Transfer - Class 7

What is Heat?

• A type of solid matter
• A form of energy
• A form of light
• A type of sound

Transfer of heat takes place between ______ bodies.

• 2

• 1

• 5

• 3

What is conduction of heat?

• Transfer of thermal energy through electromagnetic waves

• Transfer of thermal energy through the movement of fluid particles

• Transfer of thermal energy through direct contact between particles of a substance

• Transfer of thermal energy through the conversion of light energy

Explain an example of conduction of heat.

• Glass becoming hot when placed in a microwave

• Wooden spoon getting cold in a hot cup of coffee

• Plastic melting in the sun

• Metal spoon becoming warm when placed in a hot cup of coffee

What is convection of heat?

• Transfer of heat through solid objects

• Transfer of heat through electromagnetic waves

• Transfer of heat through chemical reactions

• Transfer of heat through the movement of fluids

Describe an instance of convection of heat.

• When hot air stays in one place and cold air moves

• When hot air rises and cold air sinks

• When hot air sinks and cold air rises

• When hot air turns into cold air and vice versa

What is radiation of heat?

• Transfer of heat through electromagnetic waves

• Transfer of heat through sound waves

• Transfer of heat through conduction

• Transfer of heat through mechanical waves

Provide an example of radiation of heat.

• Heat from a refrigerator

• Heat from a light bulb

• Heat from the sun

• Heat from a microwave

Identify the type of heat transfer for the group 1.

• Conduction

• Convection

• Radiation

Identify the type of heat transfer for the group 2.

• Conduction

• Convection

• Radiation