Electromagnetic waves

Question 0

X-rays

Answer 0

High energy waves from the parts of the electromagnetic spectrum between gamma rays and ultraviolet waves.

Question 1

Gamma rays

Answer 1

The highest energy wave in the electromagnetic spectrum.

Question 2

Ultraviolet radiation

Answer 2

Electromagnetic radiation just beyond the blue end of the visible light.

Question 3

Electromagnetic spectrum

Answer 3

A set of radiations that have different wavelengths and frequencies but all travel at the same speed in a vacuum.

Question 4

Wave speed

Answer 4

Speed of travel of a wave.

Question 5

Visible light

Answer 5

The part of the electromagnetic spectrum that can be detected by the human eye.

Question 6

Microwave

Answer 6

Part of the electromagnetic spectrum.

Question 7

Radio wave

Answer 7

Longest wavelength of the electromagnetic spectrum.

Question 8

Band

Answer 8

Part of radio and microwave spectrum used for communications.

Question 9

Optical fibre

Answer 9

Thin glass fibre used to send light signals along.

Question 10

Doppler effect

Answer 10

The change of wavelength ( and frequency) of the waves from source due to the motion of the source towards or away from the observer.

Question 11

Red-shift

Answer 11

Increase in the wavelength of electromagnetic waves emitted by a star or galaxy due to its motion away from us. The faster the speed of the star or galaxy, the greater the red-shift is.

Question 12

Blue shift

Answer 12

Decrease in the wavelength of electromagnetic waves emitted by a star or galaxy due to its motion towards us. The faster the speed of the star or galaxy, the greater the blue-shift is.

Question 13

Big Bang theory

Answer 13

The theory that the universe was created in a massive explosion ( the Big Bang) and that the universe has been expanding ever since.

Question 14

Cosmic microwave background radiation

Answer 14

Electromagnetic radiation that has been travelling thorough space ever since it was created shortly after the Big Bang.