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Question
Find the dimensions of Planck's constant h from the equation E = hv where E is the energy and v is the frequency.
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Solution
E = hv, where E is the energy and v is the frequency
\[\text{ Here,} \left[ E \right] = {\left[ {ML}^2 T^{- 2} \right]}\text{ and }{\left[ v \right]} = {\left[ T^{- 1} \right]}\]
\[\text{ So, }\left[ h \right] = \frac{\left[ E \right]}{\left[ v \right]} = \frac{\left[ {ML}^2 T^{- 2} \right]}{\left[ T^{- 1} \right]} = \left[ {ML}^2 T^{- 1} \right]\]
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