Mr. Putman 8th Grade Science Chapter 18

The speed of electromagnetic waves is ____.

• greater in water than in air
• different for each frequency in a vacuum
• 300,000 km/s in a space
• less for light than for x rays

The number of waves that pass a certain point in one second is the wave’s ____.

• frequency
• amplitude
• wavelength
• intensity

Sunscreen protects the skin from damage caused by ____.

• infrared waves
• visible light
• ultraviolet radiation
• all of the above

A wave transfers ____.

• energy
• matter
• vibrating electric charges
• electromagnetic energy

Electromagnetic waves are produced by ____.

• positive and negative charges
• magnetic fields
• charged particles in motion
• electromagnetic energy

Vibrating charged particles make ____ fields.

• electric
• magnetic
• radio
• both a and c

Electromagnetic waves ____.

• are compressional
• carry radiant energy
• must have a medium
• are generated by static electricty

The longest wavelength in the electromagnetic spectrum is the ____.

• gamma ray
• ultraviolet ray
• radio wave
• infrared ray

The electromagnetic waves with wavelengths slightly longer than visible light are ____.

• microwaves
• infrared waves
• ultraviolet waves
• x ray

The frequency of purple light is ____ than that of yellow light.

• higher than
• lower than
• the same as 
• faster than