The displacement due to a wave moving in the positive $x$-direction is given by $y = \frac{1}{(1 + x^2)}$ at…
The displacement due to a wave moving in the positive $x$-direction is given by $y = \frac{1}{(1 + x^2)}$ at time $t = 0$ and by $y = \frac{1}{[1 + (x - 1)^2]}$ at $t = 2\text{ s}$, where $x$ and $y$ are in metre. The velocity of the wave (in $\text{ms}^{-1}$) is
0.5
1
2
4
Solution
In a wave equation, $x$ and $t$ must be related in the form $(x \pm vt)$.
We rewrite the given equations $y = \frac{1}{1 + (x - vt)^2}$
For $t = 0$, $y = \frac{1}{(1 + x^2)}$ and