Question

Question #9a881

Answer 1

`0.88s`

Explanation:

Distance between two adjacent crests (first and second) is equal to one wavelength `lambda` as shown in the figure. Distance between six adjacent crests will be `5lambda`.
Wavelength of the given wave `lambda=220/5=44mm`
We know the wave equation
`v=nlambda` ....(1)
where `v` is velocity and `n` frequency of wave

We also know that time taken `T` for one cycle of a repeating event, is the reciprocal of the frequency.
`n=1/T`
Equation (1) thus can be written as
`v=1/Tlambda`
`=>T=lambda/v`
Inserting given numbers, convert to SI units

`T=(44/1000)/0.05=0.88s`