The Electromagnetic Spectrum

Question 1

Electromagnetic waves are________ waves and travel at the______ _______ through a vacuum

Answer 1

1. transverse

2. Same speed

Question 2

The electromagnetic spectrum

Answer 2

Radio, microwave, Infra-red, visible light, ultra violet , X Ray, gamma ray

Question 3

What are electromagnetic waves?

Answer 3

Electromagnetic waves are electric and magnet disturbances that transfer energy from one place to another.

Question 4

Infra-red

Answer 4

Infra-red is used for carrying signals from remote handsets and in optical fibres. It is also used in infra red camera and infra red scanners in hospitals

Question 5

Microwave

Answer 5

Microwaves carry mobile phone calls. Further research is needed to evaluate whether or not mobile phones are safe

Question 6

________ ________ of electromagnetic radiation have________ ____ ___ _____.

Answer 6

Different wavelength

Different effects on living cells

Question 7

Microwaves

Answer 7

Microwaves can cause internal hearing, they are called microwaves because they have shorter wavelengths than radio.

Question 8

What are microwaves used for?

Answer 8

They are used for satellite tv because they can pass through the atmosphere and reach satellites above the earth. They are also used to carry mobile phone signals.

Question 9

Radio waves

Answer 9

They have frequencies ranging from 300,000 to 3000 million hertz.

Question 10

How are radio waves produced?

Answer 10

They can be produced by oscillations in electrical circuits.

Question 11

What are radio waves used for?

Answer 11

Bluetooth enabled devices can communicate without being connected by wires. A Bluetooth radio is fitted to each device.

Question 12

What are infrared used for?

Answer 12

They are used for communications, infrared radiation is also used in remote control handsets and infrared cameras.

Question 13

Ultraviolet

Answer 13

Contain chemicals to absorb UV and emit light.

Question 14

How does an ultraviolet lamp work?

Answer 14

The ink in security marker pens is invisible until you shine a UV lamp on it.

Question 15

What are the disadvantages of using UV?

Answer 15

They can cause skin to age prematurely and increase the risk of skin cancer.

Question 16

X rays

Answer 16

X rays pass through soft tissue but are absorbed by bone.

Question 17

What are X rays used for?

Answer 17

They are used in hospitals to take radiographs (X Ray images)

Question 18

Why are X rays and gamma rays bad?

Answer 18

X rays are a type of ionising radiation which can cause the mutation of genes. This can lead to cancer.

Question 19

Gamma rays

Answer 19

Gamma rays originate from changes in the nucleus of an atom.

Question 20

What are gamma rays used for?

Answer 20

Gamma rays are used in hospital to kill cancer cells. They are also used to kill harmful bacteria and sterilise medical equipment.

Question 21

Electromagnetic waves are________ waves and travel at the_____ _____ through a vacuum(300 million m/s)

Answer 21

1. Transverse

2. same speed