P4

-transverse waves= particles move up and down at a perpendicular angle to the direction of travel. examples would be:

• water waves

• electromagnetic waves

-longitudinal waves= particles move back and forth in the direction of travel. examples:

• sound waves

-electromagnetic waves do not need a medium to pass through.

-frequency= number of waves passing a point each second.

-frequency is measured by Hertz (Hz)

-period= length of time it takes for one wave to pass a point

-wavelength= distance from one point on a wave to the same point on another wave, measured in metres (m)

-amplitude= maximum distance from the peak of the wave to the undisturbed line.

-velocity= speed of the wave in the direction its traveling in.

- FORMULA of speed= -FORMULA FOR WAVE SPEED=

-refraction= when the ray of light changes upon entering the second medium.