Uses Of Electromagnetic Waves

Question 1

Radio waves

Answer 1

Communication

Wavelength bigger than 10cm

Long RV 1 to 10 km travel far cause diffract

For TV and FM radio 10cm to 10m very short direct sight of transmitter

Short waves radio 10m to 100m reflected from ionosphere recieved at long distance

Question 2

Microwaves

Answer 2

1 to 10 cm

Satelite communication

Wavelength of microwaves can pass easily through watery atmosphere without being absorbed

Signal transmitted by transmitter into space picked up by satellite receiver dish satellite transmits signal back in different directions received by satellite dish on ground

Used in phones to nearest transmitter

Question 3

Microwaves in ovens

Answer 3

Absorbed by water molecules microwaves in microwave ovens have different wavelength

These microwaves get absorbed by water molecules penetrate a few centimetres before absorbed energy conducted or convicted to other parts

Question 4

Infrared

Answer 4

Used for heating and monitor temperature

Question 5

Lights signals

Answer 5

Travel through optical fibres used in communication

Used for telephone and broadband internet cables

Used in medical tracers to see inside the body

Also used in decorative lamps

Question 6

Ultraviolet

Answer 6

Used in fluorescent lamps movies are absorbed by it and visible light is then emitted

More efficient

Question 7

X-rays

Answer 7

Used to view internal structures of objects and materials

Bones and metals do not allow X-rays to pass through easily which is why I see the Images white

Question 8

Gamma radiation

Answer 8

Used to sterilise medical equipment and food

Good because no damage done to equipment or food perfectly safe to use or eat