WBJEE · Physics · Units and Dimensions
Which of the following quantity has the dimension of length?
(h is Planck's constant, m is the mass of electron and c is the velocity of light)
- A \(\frac{\mathrm{hc}}{\mathrm{m}}\)
- B \(\frac{\mathrm{h}}{\mathrm{mc}^2}\)
- C \(\frac{\mathrm{h}^2}{\mathrm{mc}^2}\)
- D \(\frac{\mathrm{h}}{\mathrm{mc}}\)
Answer & Solution
Correct Answer
(D) \(\frac{\mathrm{h}}{\mathrm{mc}}\)
Step-by-step Solution
Detailed explanation
\begin{aligned} & \text { Hint : }[\mathrm{h}]=\left[\mathrm{ML}^2 \mathrm{~T}^{-1}\right] \\ & {[\mathrm{c}]=\left[\mathrm{LT}^{-1}\right]} \\ & {[\mathrm{m}]=\left[\mathrm{M}^1 \mathrm{~L}^0 \mathrm{~T}^0\right]} \\ & \text { Dimension of length } \\ &…
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