2. An electromagnetic wave is a wave that consists of electric and magnetic fields that vibrate at right angles to each other.An electromagnetic wave is a wave that consists of electric and magnetic fields that vibrate at right angles to each other.

4. An electric field surrounds every charged object. You see the effect of electric fields whenever you see objects stuck together by static electricity.An electric field surrounds every charged object. You see the effect of electric fields whenever you see objects stuck together by static electricity. A magnetic field surrounds every magnet. Because of magnetic fields, paper clips and iron filings are pulled toward magnets.A magnetic field surrounds every magnet. Because of magnetic fields, paper clips and iron filings are pulled toward magnets.

5. Electromagnetic radiation is energy that travels in waves and in all directions in space.Electromagnetic radiation is energy that travels in waves and in all directions in space.

6. The entire range of EM waves is called the electromagnetic spectrum. The electromagnetic spectrum is divided into regions according to the length of the waves.The entire range of EM waves is called the electromagnetic spectrum. The electromagnetic spectrum is divided into regions according to the length of the waves.

8. Radio waves have the longest wavelengths (>30 cm) and the lowest frequencies of all EM waves.Radio waves have the longest wavelengths (>30 cm) and the lowest frequencies of all EM waves. Radio waves are used for broadcasting radio signals.Radio waves are used for broadcasting radio signals.

9. Microwaves have shorter wavelengths (1mm – 30 cm) and higher frequencies than radio waves.Microwaves have shorter wavelengths (1mm – 30 cm) and higher frequencies than radio waves.

11. Microwaves are used to send information over long distances.Microwaves are used to send information over long distances. Cellular phones send and receive signals using microwaves.Cellular phones send and receive signals using microwaves. Signals sent between Earth and artificial satellites in space are also carried by microwaves.Signals sent between Earth and artificial satellites in space are also carried by microwaves.

12. Microwaves are used in radar. Radar (RAdio Detection And Ranging) is used to detect the speed and location of objects.Microwaves are used in radar. Radar (RAdio Detection And Ranging) is used to detect the speed and location of objects. Radar sends out microwaves that reflect off an object and return to the transmitter. The reflected waves are used to calculate speed.Radar sends out microwaves that reflect off an object and return to the transmitter. The reflected waves are used to calculate speed.

13. Infrared waves have shorter wavelengths (700 nanometers (nm) and 1 mm) and higher frequencies than microwaves.Infrared waves have shorter wavelengths (700 nanometers (nm) and 1 mm) and higher frequencies than microwaves.

14. Visible light is the very narrow range of wavelengths (400 – 700 nm) and frequencies in the EM spectrum that humans eyes respond to.Visible light is the very narrow range of wavelengths (400 – 700 nm) and frequencies in the EM spectrum that humans eyes respond to.

15. Humans see different wavelengths of visible light as different colors. The longest wave-lengths are seen as red light. The shortest wave-lengths are seen as violet light.Humans see different wavelengths of visible light as different colors. The longest wave-lengths are seen as red light. The shortest wave-lengths are seen as violet light.

16. Ultraviolet waves have shorter wavelengths (60 – 400 nm) and higher frequencies than visible light.Ultraviolet waves have shorter wavelengths (60 – 400 nm) and higher frequencies than visible light.

17. Too much UV light can cause sunburn. UV light can also cause skin cancer and wrinkles, and damage the eyes.Too much UV light can cause sunburn. UV light can also cause skin cancer and wrinkles, and damage the eyes. Ultraviolet waves produced by UV lamps are used to kill bacteria on food and surgical tools. Small amounts of UV light are beneficial to your body, causing skin cells to produce vitamin D.Ultraviolet waves produced by UV lamps are used to kill bacteria on food and surgical tools. Small amounts of UV light are beneficial to your body, causing skin cells to produce vitamin D.

18. X Rays have wavelengths between 0.001 nm and 60 nm. X rays can pass through many materials, making them useful in the medical field.X Rays have wavelengths between 0.001 nm and 60 nm. X rays can pass through many materials, making them useful in the medical field. However, too much exposure to X rays can damage or kill living cells.However, too much exposure to X rays can damage or kill living cells.

20. Gamma Rays have wavelengths shorter than 0.1 nm. They can penetrate most materials easily.Gamma Rays have wavelengths shorter than 0.1 nm. They can penetrate most materials easily. Gammas rays are used to treat some forms of cancer. Doctors focus the rays on tumors inside the body to kill the cancer cells.Gammas rays are used to treat some forms of cancer. Doctors focus the rays on tumors inside the body to kill the cancer cells. Gamma rays are also used to kill harmful bacteria in foods, such as meat and fresh fruits.Gamma rays are also used to kill harmful bacteria in foods, such as meat and fresh fruits.