Answer : Time period will be 0.5 seconds.
Explanation : We can use the formula as;
f = c / λ
f = wave speed c (units m/s) / wavelength λ (units m).
Here, c = 40 and λ = 20;
f = 40 / 20 = 2 Hz
The formula for finding time period is:
\(T (period) = \frac{1}{f}\) where f = frequency
We have, f = 2 Hz;
\(T (period)= \frac{1}{2}\) = 0.5 second.
Therefore, time period will be 0.5 seconds.
