A source is producing 20 waves in 4 sec. The distance between a crest and a trough is 12 cm. Find
the velocity of the wave

Explanation

To find the velocity of the wave, we can follow these steps:

### Step 1: Calculate the Frequency
The frequency (f) of the wave can be calculated using the formula:
\[ f = \frac{\text{Number of waves}}{\text{Time taken}} \]

Given that the source produces 20 waves in 4 seconds:
\[ f = \frac{20 \text{ waves}}{4 \text{ seconds}} = 5 \text{ Hz} \]
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