The value of Planck's constant is

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Question

(B) Planck's constant $(h)$ relates the energy of a photon to its frequency according to the equation $E = h 
u$.Since $E$ is measured in Joules $(J)

Vedclass · Accepted Answer

$6.63 	imes 10^{-34} \; kg \cdot m^2 / s$

Vedclass · Answer

(B) Planck's constant $(h)$ relates the energy of a photon to its frequency according to the equation $E = h 
u$.Since $E$ is measured in Joules $(J)$ and frequency $
u$ is in $s^{-1}$,the unit of $h$ is $J \cdot s$.Alternatively,since $E = 	ext{Force} 	imes 	ext{Distance} = (kg \cdot m/s^2) 	imes m = kg \cdot m^2/s^2$,then $h = E/
u = (kg \cdot m^2/s^2) / (1/s) = kg \cdot m^2/s$.The numerical value of Planck's constant is approximately $6.63 	imes 10^{-34} \; J \cdot s$ or $6.63 	imes 10^{-34} \; kg \cdot m^2/s$.Comparing this with the given options,option $B$ represents the correct value and units.

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