Understanding Heat Energy

What is the primary source of heat energy for the Earth?

• The Moon

• The Stars

• The Sun

• Electricity

Which of the following is a method of producing heat through friction?

• Boiling water

• Burning a candle

• Rubbing hands together

• Using an electric stove

Which activity does NOT produce heat?

• Reading a book

• Burning wood

• Rubbing hands

• Using electricity

How does heat from the Sun affect the Earth's surface during the day?

• It makes it rain

• It has no effect

• It warms it up

• It cools it down

Without the Sun's heat, what would happen to the Earth?

• Plants would grow faster

• The Earth would explode

• Aliens would invade

• It would be too cold to survive