P5.2 - Electromagnetic Spectrum

Question 1

Our eyes are only sensitive to

Answer 1

Visible Light, which is not absorbed by the atmosphere.

Question 2

What are electromagnetic waves?

Answer 2

Oscillating electric and magnetic fields, which oscillate at 90 degrees.

Question 3

How do you work out the frequency of a wave?

Answer 3

Wave Speed/Wavelength

Question 4

What types of light have a higher wavelength than visible light?

Answer 4

Radio waves, microwaves and infrared.

Question 5

What types of light have a smaller wavelength than visible light?

Answer 5

Ultraviolet, X-rays and gamma rays.

Question 6

Why is ultraviolet radiation dangerous?

Answer 6

It can damage the DNA in you cells of the skin, potentially causing skin cancer.

Question 7

How are X-rays used for imaging?

Answer 7

Bones absorbs many X-rays, but soft tissue like skin and muscle do not. Photographic film darkens upon absorbing X-rays, showing the internal details of a person.

Question 8

How are gramma rays used for imaging?

Answer 8

A patient gets injected with a radioactive substance which emits gamma rays. A sensor detects these gamma rays.