Light

Question 1

When rays of light pass through a transparent medium to another

Answer 1

They change speed

If entering the medium at an angle other than 90 degrees to the surface, they change direction

Question 2

Air- glass

Answer 2

Towards the normal

Question 3

Glass- air

Answer 3

Away from the normal

Question 4

If the incident ray is the same as the critical angle

Answer 4

The ray is refracted along the interface (angle of refraction = 90 degrees)

Question 5

If the incidence ray is bigger than the critical angle

Answer 5

Total internal reflection occurs

Question 6

Total internal reflection occurs when

Answer 6

Light is travelling from a more dense medium to a less dense. Medium

The angle of incidence is greater than the critical angle

Glass- air

Question 7

transverse waves

Answer 7

the particles of the medium vibrate in a direction perpendicular to the direction in which the wave is being propagated

Question 8

examples of transverse waves

Answer 8

all electromagnetic waves and water waves

Question 9

longtiundial waves

Answer 9

the particles of the medium vibrate in a direction parallel to the direction of propagation of the wave

Question 10

examples of longtiundial waves

Answer 10

sound waves, primary seismic waves

consist of compressions and rarefractions

Question 11

compressions

Answer 11

a region where the particles of the medium move towards each other giving areas of increased pressure

Question 12

rarefraction

Answer 12

a region where the particles of the medium have moved away fromm each other, giving an area of decreased pressure.

Question 13

the electromagnetic spectrum is arranged in order of

Answer 13

long wavelength, low frequency low energy (radio waves)

Question 14

radio waves

Answer 14

used for broadcasting and communication

Question 15

microwaves

Answer 15

used for cookers and satellite transmittions

bad effect- internal heating of body tissue

Question 16

infra-red

Answer 16

heaters and night vision
effect on body- skin burns
to limit the effect- avoid radiation, wear suitable clothes

Question 17

visible light

Answer 17

optic fibers and photography
effect on body- eye damage
limit- avoid radiation, wear sunglasses

Question 18

x rays

Answer 18

a photographic or digital image of the internal composition of something,

effect- damage and possible mutation of cells, could cause cancer

limit- avoid radiation, use protective shielding

Question 19

ultraviolet

Answer 19

fluorescent lamps
effect- damage to surface cells and blindness
limit- avoid radiation, wear suitable clothes and sunglasses

Question 20

gamma rays

Answer 20

sterilising food and medial equipment
effect- damage and possible mutation of cells, which could cause cancer
limit- avoid radiation. use protective shielding

Question 21

waves transfer

Answer 21

energy and information without transferring matter

Question 22

all of the electromagnetic sectrum

Answer 22

are transverse waves
can transmit energy 
have the same speed
can travel through vacuum
can all be reflected

Question 23

the height of the wave is

Answer 23

amplitude

Question 24

the length of the wave is

Answer 24

wavelength

Question 25

the top is called

Answer 25

crest

Question 26

the bottom is called

Answer 26

trough

Question 27

diff between transverse and longititunal

Answer 27

up and down is transverse

acorss is longtitiundail

Question 28

thing the electromagnetic spectrum all share but no other waves do

Answer 28

same speed in a vacuum

travel at the speed of light

Question 29

what does the critical angle mean

Answer 29

the angle at which refraction just occurs

Question 30

how can you increase the amplitude of a wave

Answer 30

increasesize of vibration

Question 31

how can you increase the wavelength

Answer 31

increase frewuecy