Electromagnetic Spectrum: Microwaves and Infrared Radiation

What characteristic of microwaves allows them to be used for satellite communication?

• They have short wavelengths.

• They can pass through the Earth's atmosphere.

• They are absorbed by water molecules.

• They have high frequencies.

How do microwaves heat food in a microwave oven?

• By heating the air around the food.

• By vibrating water molecules in the food.

• By directly heating the food's surface.

• By using infrared radiation.

What is a common use of infrared cameras?

• To see in the dark by detecting heat.

• To emit visible light.

• To measure radio waves.

• To detect sound waves.

Why does bread toast in a toaster rather than just getting warmer like in a microwave?

• Because the toaster uses sound waves.

• Because microwaves are used in toasters.

• Because infrared radiation heats the surface of the food.

• Because infrared radiation penetrates the food deeply.

What happens to living cells when exposed to high levels of microwave radiation?

• They boil and are destroyed.

• They become magnetic.

• They freeze.

• They emit light.