# Example questions

In the following diagram the waves move from left to right and then stop. The motion of the waves lasts for two seconds.

A 2 second wave with 2 peaks and troughs.

Question

What is the amplitude of the waves?

The amplitude of the waves is 0.4 metres ($$40cm$$) - from the centre line to the top of a crest.

Question

What is the wavelength of the waves?

The wavelength of the waves is two metres - from one crest to the next crest along.

Question

How many waves are shown on the diagram?

So how many waves are generated in the two seconds?

So what is the frequency of the waves?

Two waves are shown on the diagram.

So two waves are generated in the two seconds.

So the frequency of the waves is 1 hertz - 1 wave per second.

Question

What is the wave speed?

The wave speed is two metres per second - the waves travel four metres in two seconds.

Wave calculations

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