p6. waves Flashcards
1
Q
name all properties of a wave
A
- peak = highest point of wave
- trough = lowest point of wave
- amplitude = distance from starting line ( rest position ) to top of wave
- wavelength = distance from one wave to another
( peak - peak / trough - trough ) - time period = time taken for full cycle of a wave
- frequency = number of waves passing per second
2
Q
what is wave speed?
A
the speed energy is transferred ( waves moving ) through the medium
3
Q
RP : measure the frequency, wavelength and speed of waves in a ripple tank and waves in a solid
A
- set up ripple tank with 5cm depth of water
- adjust height of wooden rod to be touching surface of water
- turn on lamp and motor , adjust until low frequency waves can be observed
- record wave length - better to take photo with a ruler and measure
- calculate frequency
- calculate wavespeed
4
Q
what are transverse waves?
A
waves which oscillate perpendicular to direction
5
Q
what are electromagnetic waves?
A
transverse waves which transfer energy from the source of the waves to an absorber
6
Q
name electromagnetic spectrum ( low frequency - high frequency ) / ( long wavelengh - short wavelength )
- give examples of uses for each
A
- radiowaves = broadcasting and communication
- microwaves = cooking and mobile phones
- infared = remote controls and thermal imaging
- visible light = photography
- ultraviolent = sterilising water and tanning
- xrays = medical imaging and airport security
- gamma rays = radiotherapy and sterilising medical equipment
7
Q
RP : the amount of infrared radiation absorbed or radiated
A
- place a leslie cube on heat-resistant mat
- fill with boiling water and replace lid
- leave for one minute - enables surface to heat up to temperature of water
- used infared detector to measure intensity of infared radiation emitted from each surface / temperature of surface
- make sure detector is same distance from each surface for each reading
- plot on bar graph to help order from best emitter to worst emitter
