3rd Grade Energy - Heat & Light

Heat is a form of ____________
The main source of the Earth's heat is:
1. firewood
2. the Sun
3. the Moon
4. electricity
Heat can move through
1. liquids
2. gases
3. solids
4. space
5. all of the above
An instrument we can use to measure the temperature of something is the _____________ .
At the beach, which needs more heat energy to increase its temperature?
1. water
2. sand
When matter loses heat, its particles:
1. speed up
2. slow down
3. stay the same
When matter heats up, it usually will __________ .
1. contract (gets smaller)
2. expand
3. neither
Heat can flow. Which statement is true?
1. Heat always flows from warmer objects to cooler objects.
2. Heat always flows from cooler objects to warmer objects
A material that heat does not move quickly through is called an ____________ .
Check all the items below that are good heat conductors.
1. iron
2. wool
3. aluminum
4. fur
5. copper
An electric toaster is a good example of a device that changes electrical energy into heat energy.
1. True
2. False
When fuel is burned, _____________ is given off.
The primary source of energy for our bodies to keep the same body temperature is ____________ .
Light is a form of _____________ .
Unless it is affected by other forces, light travels in _______________ .
1. curved lines
2. circular paths
3. straight lines
Check all the 'natural' light sources:
1. the Sun
2. light bulbs
3. the stars
4. candles
5. lightning
Check the materials that are opaque (block light rays):
1. air
2. bricks
3. glass
4. metals
5. wood
Check the objects below that would 'reflect' light rays well:
1. your driveway
2. the bathroom mirror
3. the carpet on the floor
4. a shinny aluminum pot
When light rays pass through curved gless, they
1. stay in a straight line
2. bend or refract
The light from the Sun
1. is all white light
2. is all yellow light
3. is a mixture of many colors