Wave transfer………without transferring……..
Waves transfer energy without transferring matter
What are the two types of waves
Transverse longitudinal
What is a transverse wave
The vibrations are at 90 degrees to the direction of energy transfer
What is a longitudinal wave
The vibrations are parrellel to the direction of energy
Example of longitudinal wave
Sound
Example of transverse wave
Light
,EM waves
Define these terms amplitude,frequency,wavelength
• Amplitude: the maximum displacement of a wave from its rest position.
• Frequency: the number of waves per second (measured in hertz, Hz).
• Wavelength: the distance between two corresponding points on a wave (e.g. crest to crest).
What is the difference between a sound and light wave
Sound-longitudinal,slower
Light-transverse, faster
What is refraction?
Refraction is the bending of a wave as it passes from one medium to another
What are the uses of all the EM waves
Radio-communication through earth
Infared-heating food/measuring heat
Visible light-transferring data through optical fibres
UV-tanning
X-rays-seeing broken bones
Gamma-sterilisation by killing cells
In the Leslie cube experiment what are the IV DV CV
IV-type of surface
DV-Amount of infrared emitted
CV-distance from the cube
What do all EM waves have in common
All transverse waves
Travel at the speed of light through a vacuum
All can travel through a vacuum
What is the equation for working out wave speed
Wave speed=dispacement/time
Which type of material emit radiation better?
Darker ones
Matt black is the best
Which EM waves are harmful
Why?
UV,Xray,gamma rays
Knock electrons off of atoms and cause mutations to cells which then causes cancer
How can you measure wavelength
Crest to crest
How can you measure frequency
Amount of successful waves that pass a point in a given amount of time
How can you make the measurements more accurate
Use better equipment (machine)
Do it multiple times or for a longer duration of time
