Q15 (b)

A sound wave can be modelled using a function $P(t)=k\sin(at)$, where $P$ is air pressure in Pascals, $t$ is time in milliseconds (ms) and $k$ and $a$ are constants.

The graph of $P_1(t)$ from part (a) is shown.

On the diagram, sketch the graph of

$$P_2(t)=4\sin\left(\frac{\pi}{10}t\right)$$

for $0\leq t\leq10$.