Question

Two sinusoidal waves with same wavelengths and amplitudes travel in opposite directions along a string with a speed `10ms^-1`. If the minimum time interval between two instant when the string is flat is `0.5s`, the wavelength of the waves is
A. `25m`
B. `20m`
C. `15m`
D. `10m`

Answer 1

Correct Answer - D
Minimum time interval between two instant when the string is flat`=(T)/(2)=0.5secimpliesT=1sec`
Hence `lamda=vxxT=10xx1=10m`.