waves

Question 1

amplitude

Answer 1

distance from rest point to crest

Question 2

wavelength

Answer 2

full cycle of the wave

Question 3

frequency

Answer 3

number of waves through a point each second

or the number of waves rom the source per second

Question 4

transverse waves

Answer 4

move up and down 90 degrees to the direction of the wave
light and all em waves
waves on string
ripples on water

Question 5

longitudinal waves

Answer 5

particles move parallel to direction of wave

sound waves and ultrasound

Question 6

rarefraction

Answer 6

spread out

Question 7

compressions

Answer 7

clumps on particles

Question 8

wave speed =

Answer 8

frequency x length

Question 9

drawing ray diagrams key points

Answer 9

the image is the same size
image is the same distance behind the mirror than in front
the image is virtual and upright
laterally inverted- the left and right side switch

Question 10

diffraction

Answer 10

the waves spread out when they pass through gap or pass an object

Question 11

amount of diffraction depends on…

Answer 11

the size of the gap relative to the length of the wave

small gap and long wave= lots of diffraction

Question 12

diffraction rates

Answer 12

if the gap is the same as or smaller than the WAVELENGTH of a wave not amplitude

Question 13

refraction key works

Answer 13

medium- the substance
incident ray
refracted ray
emergent ray

Question 14

em spectrum

Answer 14

7 basic types but they merge into a continuous spectrum

vary between 10 to the -15 ——– 10 to the 4 in wavelength

Question 15

em waves speed

Answer 15

travel at the same speed
higher frequency= shorter wavelength
different wavelengths= different properties

Question 16

uses of long radiowaves

Answer 16

can be sent around world as they diffract around the earth- radio waves
can diffraction around hills and into tunnels

Question 17

use of short wavelengths

Answer 17

cant diffract so have to be in direct line of transmitter
get around by reflecting off ionosphere- electrical charged layer of earth’s atmosphere
medium wavelengths can also be reflected- depending on weather

Question 18

microwaves uses

Answer 18

satellites- can pass through watery atmosphere

Question 19

microwaves health risks

Answer 19

heat up water in your cells

Question 20

other uses of microwaves satellites

Answer 20

“remote sensing” satellites- used to see through clouds and track oil spills, icebergs movement and deforestation

Question 21

infrared rays uses

Answer 21

wireless controllers- emit different patterns of rays for different commands
optical fibres- use infrared and visible light rays
pulses of rays are reflected off the sides of the core of the fibre very quickly

Question 22

cameras

Answer 22

lens used to focus light onto a light sensitive film or electronic sensor
the lens APERTURE controls how much light enters the camera
shutter speed determines the exposure to the light

Question 23

sound waves causes

Answer 23

vibrating through objects
heard when travelling through someone’s inner ear and reaches the eardrum
denser the medium- the faster the object travels through
sound cant travel in space

Question 24

higher frequency =

Answer 24

higher pitch

frequency= number of complete vibrations per second

Question 25

higher amplitude =

Answer 25

louder the sound