 # Wave properties for Edexcel GCSE Physics 1. Wave amplitude
2. Wavelength
3. Wave frequency
4. Wave period
5. Wave speed

A wave’s amplitude is a measure of its maximum height from its rest position. The wavelength (λ) of a wave can be shown in a diagram or it can be calculated using the formula: Wavelength = wave speed ÷ frequency. The frequency of a wave is the number of waves that pass a certain point per second. It can be calculated using the waves time period, or speed and wavelength. The time period of a wave is the time it takes a full wave cycle to pass a certain point. It is often calculated using the equation: Time Period = 1 ÷ frequency. Wave speed is the distance travelled by a wave divided by the time it takes. The wave equation can be used to work out the speed of a wave. # 1

Using the diagram, calculate the speed of the wave shown if it has a wavelength of 25 m.

Speed = Wavelength ÷ Time Period. V = λ ÷ T, V = 25 ÷ 10 = 2.5 m/s. # 2

The vertical displacement of a point on a wave doubles when the amount of energy in the wave doubles. What is the effect on the amplitude of the wave?

It doubles. # 3

What is the definition of wavelength?

The wavelength is the distance covered by a full cycle of a wave, this is usually measured as the distance between two peaks or two troughs. # 4

In the diagram each line represents the peak of a wave, what is the wavelength of the waves shown?

4 cm # 5

Define wave speed.

The speed of a wave is the amount of distance a wave has travelled in a given time interval. End of page