Question

A wave is 2.30 m long before transmission. After transmission, it is  travelling at 5.26 m/s with a wavelength of 1.75 m. What is the velocity  of the wave before transmission? 

Answer 1

Before transmission

l=$\lambda$ =2.30m

after transmission

$\lambda=1.75m$

$V=5.26m/sec$

$V=n\lambda$

$n=\frac{V}{\lambda}$

$n=\frac{5.26}{1.75}=3Hz$

Before transmission and after transmission wave frequency not change

Before transmission

$V=n\lambda$

$V=3\times2.30=6.9m/sec$