Question

A travelling harmonic wave is represented by the equation $y(x,t)=10^{-3}sin(50t+2x)$, where $x$ and $y$ are in meter and $t$ is in seconds. Which of the following is a correct statement about the wave?
The wave is propagating along the

• A. negative x-axis with speed $25m{s}^{-1}$
• B. The wave is propagating along the positive x-axis with speed $25m{s}^{-1}$
• C. The wave is propagating along the positive x-axis with speed $100m{s}^{-1}$
• D. The wave is propagating along the negative x-axis with speed $100m{s}^{-1}$

Answer 1

Answer: (A)

$y=a\sin (\omega t+kx)$
$\Rightarrow$ wave is moving along $-ve$ x-axis with speed
$v=\frac{\omega }{K}\Rightarrow v=\frac{50}{2}=25m/\sec$