Waves period, frequency and velocity
Name: ________________ Date: ___________
The period of a wave is the time it takes for one full wavelength. It is measured
in seconds (s) and has the symbol T.
The frequency of a wave is the number of waves per second. It is measured in
hertz (Hz) and has the symbol 𝑓.
Period and frequency are inversely proportional to each other (reciprocals).
That means as one increases the other decreases and vice versa. As a formula:
𝑓𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 =
1
𝑝𝑒𝑟𝑖𝑜𝑑
or
𝑓=
1
𝑇
1) Find the amplitude of P, Q and R.
2) Find the period of P, Q and R.
3) Calculate the frequency of P, Q and R.
The velocity of a wave is how fast the wave is travelling. It is measured in
metres per second (m/s) and has the symbol v.
The wavelength of a wave is the distance between two corresponding points in
a wave, usually taken from crest to crest or trough to trough. It is measured in
metres (m) and has the symbol 𝜆 (lambda).
The wave equation describes the relationship between velocity, frequency and
wavelength:
𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦 = 𝑓𝑟𝑒𝑞𝑢𝑒𝑛𝑐𝑦 × 𝑤𝑎𝑣𝑒𝑙𝑒𝑛𝑔𝑡ℎ
or
𝑣 = 𝑓𝜆
4) Find the wavelengths for P, Q and R above if their velocities are 100 m/s.
5) Find the amplitude and wavelength of the above wave.
6) If it took 10 seconds for the above wave to pass, calculate its period,
frequency and velocity.