Electromagnetic Spectrum

Question 1

What kind of waves are transverse waves?

Answer 1

transverse

Question 2

What speed do the waves travel at through a vacuum?

Answer 2

travel at the same speed through a vacuum but they travel at different speeds in different materials

Question 3

Wave order from long wavelength and low frequency to short wavelength and high frequency?

Answer 3

Radio waves, micro waves, infrared waves, visible light, ultraviolet light, x rays, gamma rays

Question 4

What do all the waves transfer energy to and from?

example

Answer 4

from a source to an absorber
when you warm yourself by an electric heater, infrared waves transfer energy from the thermal energy store of the heater to your thermal energy store

Question 5

the higher the frequency the more…

Answer 5

energy it transfers so it is more dangerous for humans

Question 6

Radio Waves - transmitted, absorbed, reflected, refracted

Answer 6

through the body being absorbed

Question 7

Microwaves- transmitted, absorbed, reflected, refracted

Answer 7

Can be absorbed, causing heating of cells which can be dangerous

Question 8

Infrared and Visible Light - transmitted, absorbed, reflected, refracted

Answer 8

Mostly reflected or absorbed by the skin, causing some heating too. IR can cause skin burns if skin gets too hot

Question 9

Ultraviolet Light - transmitted, absorbed, reflected, refracted

Answer 9

Absorbed by the skin - has a higher frequency so It is more dangerous - ionising radiation and when absorbed it can damage skin cell - skin cancer or eye damage

Question 10

X rays and Gamma Rays - transmitted, absorbed, reflected, refracted

Answer 10

Ionising radiation- can cause mutations and damage to cells - they have higher frequencies so transfer more energy so can do more damage to deeper tissue

Question 11

Radio Waves - what are they made up of?

Answer 11

oscillating electric and magnetic fields - alternating currents are made up of oscillating charges - they produce a oscillating electric and magnetic fields

Question 12

Radio waves - how do you produce them?

Answer 12

using an alternation current in an electrical circuit. The object which charges electrons oscillate to create a transmitter

Question 13

What are long radio waves used for?

Answer 13

Communication and broad casting for round the world - they bend round curved earth surface

Question 14

What are short radio waves used for?

Answer 14

communication and broadcasting for far away - as they are reflected by the earths atmosphere
bluetooth

Question 15

What are microwaves used for?

Answer 15

Cooking, communications and satellite transmissions

Question 16

What are infrared used more?

Answer 16

cooking, thermal range, optical fibres, tv remotes and security systems

Question 17

What is visible light used for?

Answer 17

Photography, vision and illumination

Question 18

What is ultraviolet used for?

Answer 18

Security marking, fluorescent lamps, detecting forged bank notes

Question 19

What are X rays used for?

Answer 19

Medical x rays, airpot security scanners

Question 20

What are gamma rays used for?

Answer 20

Sterilising food and medical equipment, the detection of cancer and its treatment

Question 21

Changes in atoms and nuclei can generate…

be caused by…

Answer 21

radiations over a wide frequency range

absorption of range of radiations

Question 22

How do microwaves heat up food?

Answer 22

microwaves need to be absorbed by water molecules in food - the microwaves penetrate into the food before being absorbed and transferring energy to water molecules causing the water to heat up- then transfer energy to rest of the molecules

Question 23

How do infrared cameras work?

Answer 23

The camera detects the IR radiation and turns it into an electrical signal which is displayed on screens as a picture

Question 24

How do digital cameras work?

Answer 24

They contain image sensors, which detect visible light and generate electrical signal - this is converted to an image that can be stored digitally

Question 25

How do fluorescent lights work?

Answer 25

use UV light to emit visible light

Question 26

How do X rays images work?

Answer 26

X ray radiation is directed at an object onto a detector plate.

Question 27

How do gamma rays sterilise medical equipment and food?

Answer 27

they kill microbes

Question 28

How do gamma rays treat cancer?

Answer 28

radiation is targeted at cancer cells to kill them