Question

The dimensional formula of Planck's constant $(h)$ is

• A. $\left[M{L}^{-2}{T}^{-3}\right]$
• B. $\left[M{L}^2{T}^{-1}\right]$
• C. $\left[ML{T}^{-2}\right]$
• D. $\left[M{L}^{-2}{T}^{-1}\right]$

Answer 1

Answer: (B)

away from the coil (Lenz's law).
Hence, acceleration of the falling magnet is less than $g$.
From Planck's law, energy of a photon of frequency $v$ is given by $E=hv$
where $h$ is Planck's constant.
$\therefore$ Dimensions of $h=\frac{\text{ Dimensions of }E}{\text{ Dimensions of }v}$
Dimensions of $h=\frac{\left[M{L}^2{T}^{-2}\right]}{\left[T^{-1}\right]}$
$\left[M{L}^2{T}^{-1}\right]$