Question

a source produce 30 crests and 30 troughs in 0.3 second.find out frequency of wave produce.

Answer 1

hope it will help you to understand..
2nd 1 is a another example

Answer 2

Given :

A source produce 30 crests and 30 troughs in 0.3 second .

To Find :

The frequency of wave .

Solution :

30 crests is produced in 0.3 seconds .

So , 1 crest will produce in i.e the Time Period is ,  $T=\dfrac{0.3}{30}=0.01\ s$

Now , we know frequency is given by :

$f=\dfrac{1}{T}\\\\f=\dfrac{1}{0.01}\\\\f=100\ Hz$

Therefore , The frequency of wave produced is 100 Hz .

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Waves

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