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The value of Planck's constant is : -
A
$6.63 \times 10^{-34}$ J/s
B
$6.63 \times 10^{-34}$ kg m$^2$/s
C
$6.63 \times 10^{-34}$ kg m$^2$
D
$6.63 \times 10^{-34}$ J s$^{-1}$
Detailed Solution
From $E = h\nu$: $h = \dfrac{E}{\nu}$, so its unit is joule/(1/second) = J s.
1 J = 1 kg m$^2$ s$^{-2}$, so J s = kg m$^2$ s$^{-2}$ $\times$ s = kg m$^2$ s$^{-1}$.
So $h = 6.63 \times 10^{-34}$ J s $= 6.63 \times 10^{-34}$ kg m$^2$/s.
J/s and J s$^{-1}$ are units of power, not of Planck's constant.
1 J = 1 kg m$^2$ s$^{-2}$, so J s = kg m$^2$ s$^{-2}$ $\times$ s = kg m$^2$ s$^{-1}$.
So $h = 6.63 \times 10^{-34}$ J s $= 6.63 \times 10^{-34}$ kg m$^2$/s.
J/s and J s$^{-1}$ are units of power, not of Planck's constant.