Two sinusoidal waves with same wavelengths and amplitudes travel in opposite directions along a string with…

Two sinusoidal waves with same wavelengths and amplitudes travel in opposite directions along a string with a speed $10\text{ ms}^{-1}$. If the minimum time interval between two instants when the string is flat is $0.5\text{ s}$, the wavelength of the waves is
  1. (a) $25\text{ m}$
  2. (b) $20\text{ m}$
  3. (c) $15\text{ m}$
  4. (d) $10\text{ m}$

Solution

Minimum time interval between two instants when the string is flat $= \frac{T}{2} = 0.5\text{ s} \Rightarrow T = 1\text{ s}$ Hence, $\lambda = v \times T = 10 \times 1 = 10\text{ m}$

Practice more Waves and Sound questions on Aicharya