(a(i))[1]
Define power in physics.
(a(ii))[1]
Use the definition of power to demonstrate that the SI base units of power are $\text{kg m}^2\text{ s}^{-3}$.
(b)[3]
For a sound wave travelling through a gas, the intensity $I$ is given by $I = f^2 A^2 v k$, where $f$ represents the frequency of the wave, $A$ the amplitude of the wave, $v$ the speed of the wave and $k$ a constant that depends on the gas. Determine the SI base units of $k$.