Question

The dimensions of the quantity $ hv/c, $ where h is Plancks constant, v is the frequency and c is the velocity of light is:

• A. $ [M{{T}^{-1}}] $
• B. $ [ML{{T}^{-1}}] $
• C. $ [ML{{T}^{-2}}] $
• D. $ [M{{L}^{2}}{{T}^{2}}] $
• E. $ [M{{L}^{-2}}{{T}^{-2}}] $

Answer 1

Answer: (B)

The Dimensions of $ h=[M{{L}^{2}}{{T}^{-1}}] $ Dimensions of $ v=[{{T}^{-1}}] $ Dimensions of $ c=[L{{T}^{-1}}] $ Dimensions of $ \frac{hv}{c}=\frac{[M{{L}^{2}}{{T}^{-1}}][{{T}^{-1}}]}{[L{{T}^{-1}}]} $ $ =[ML{{T}^{-1}}] $