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3 years ago

A source produces 20 crests and 20 troughs in 4 seconds. The second crest is 3 cm away from the first crest.Calculate :

Physics

1 answer:

sineoko [7]3 years ago

3 0

Answer:

Solution given:

No of waves[N] =20crests & 20 troughs

=20waves

Time[T]=4seconds

distance[d]=3cm=0.03m

Now

Wave length=3cm=3 × ${10}^{ - 2}m$

Frequency= $\frac{No of waves}{time}$

= $\frac{20}{4}$ =5Hertz

and

Wave speed:wave length×frequency=3 × ${10}^{ - 2}m$ ×5=1.5 × ${10}^{ - 1} \tt{ {ms}^{ - 1}}$ .

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