The Planck’s constant (h) can be defined as a proportionality constant that relates the energy (E) of a photon to the frequency (ν) of its associated electromagnetic wave.
Mathematically,
Planck’s Constant (h) = Energy(E) / frequency (ν).
Dimensional Formula of energy = M1L2T-2.
Dimensional Formula of frequency = M0L0T-1.
Putting these values in above equation we get,
Dimensional Formula of Planck’s constant = M1L2T-1.
SI unit of Planck’s constant is joule-seconds (j-s).