Waves Flashcards
What are metres measured in?
m
What are metre/second measured in?
m/s
What is a mechanical wave?
Waves that need a material medium to travel through: gas, liquid or solid
What is an electromagnetic (EM) wave?
Waves that can travel through a vacuum- they do not need matter like mechanical waves
What do waves do?
Waves transfer energy and information from one place to another. Energy and information are transferred by waves without transfer of matter.
What types of mechanical wave are there?
Transverse and Longitudinal
What is a transverse wave?
In transverse waves the medium moves at right angles to the direction of motion of the wave.
Give an example of a transverse wave?
Ripples on a pond
What is a longitudinal wave?
In longitudinal waves the medium moves in the same direction as the motion of the wave
Give an example of a longitudinal wave?
Sound waves
What are degrees measured in?
Deegeee
What happens in both types of mechanical wave?
In both types of mechanical wave, the particles that make up the medium oscillate (move back and forth) about fixed points within the medium. The difference is how the direction of their movement compares with the direction of the resultant wave travelling through the medium.
What can be done to waves?
Waves can be reflected, refracted and diffracted
What is diffraction?
Diffraction is the spreading of waves as they pass by the edges of obstacles, through a narrow gap or goes past an object.
What waves does diffraction occur with?
Diffraction occurs with all types of waves, e.g. sound waves and light waves
Are any properties of the wave changed by diffraction?
None of the properties of a wave are changed by diffraction. The wavelength, frequency, period and speed are same before and after diffraction. Again, the only change is the direction in which the wave is travelling.
Where is the greatest effect in diffraction?
When a wave passes through a gap the diffraction effect is greatest when the width of the gap is about the same size as the wavelength of the wave.
What is refraction?
Refraction occurs when a wave moves from one material to another
Are any properties of the wave changed by refraction?
The speed and wavelength are changed by refraction. The frequency and period of the wave stay the same. The direction in which the wave is travelling may or may not be changed by refraction.