Question

The time period of a periodic wave is 0.02 seconds. At a particular position there is a crest at t=0. At what value of 't' will the next trough appear at this position?

• A. 0.05 s
• B. 0.01 s
• C. 0.15 s
• D. 0.25 s

Answer 1

The correct option is B 0.01 s

$T=0.2s$

at $t=0$

there is a crest, and the figure of wave which represent the following data.

We know from the question that next crest will occur $0.02s$. And hence, the trough occur at the mean of two creast i.e.

time of trough$=\frac{0.0+0.02}{2}$

$=0.01sec$

$\therefore$ Option (B) is the correct answer.