Question

The ratio of the dimensions of Planck's constant and that of the moment of inertia is the dimension of:

• A. frequency
• B. velocity
• C. angular momentum
• D. time

Answer 1

Answer: (A)

frequency

Answer 2

$E = h v$, where $h$ is the Planck constant, is a known equation.
$h$ has a dimension of $\frac{E }{ v}$ =$\frac{ [ M L^2 T^{-2} ]}{[ T ^{-1} ]}$ = $[ M L^2 T^{-1 }]$
The moment of inertia's dimension is $[ M L^2 ]$.
The ratio is $\frac{ [ M L^2 T^{-1} ]}{[M L^2 ]} = [T^{-1}]$
dimension of Frequency = $[T^{-1}]$

Therefore, the correct option is (A): frequency.