JEE Main 2025 — Units and Dimensions Question with Solution
JEE Main 2025 (4 Apr Shift 2)
Question
Given below are two statements :
Statement (I) : The dimensions of Planck's constant and angular momentum are same.
Statement (II) : In Bohr's model electron revolve around the nucleus only in those orbits for which angular momentum is integral multiple of Planck's constant.
In the light of the above statements, choose the most appropriate answer from the options given below :
Statement (I) : The dimensions of Planck's constant and angular momentum are same.
Statement (II) : In Bohr's model electron revolve around the nucleus only in those orbits for which angular momentum is integral multiple of Planck's constant.
In the light of the above statements, choose the most appropriate answer from the options given below :
Choose an option
Show full solutionCorrect option: C
Correct answer
CStatement I is correct but Statement II is incorrect
Step-by-step explanation
$\begin{aligned}
& \mathrm{E}=\mathrm{hf} \\ & \mathrm{ML}^2 \mathrm{~T}^{-2}=[\mathrm{h}] \times\left[\mathrm{T}^{-1}\right] \\ & {[\mathrm{h}]=\left[\mathrm{ML}^2 \mathrm{~T}^{-1}\right]} \\ & \mathrm{L}=[\mathrm{MVR}]=\left[\mathrm{ML}^2 \mathrm{~T}^{-1}\right] \\ & \mathrm{L}=\frac{\mathrm{nh}}{2 \pi}
\end{aligned}\frac{\mathrm{h}}{2 \pi}$
& \mathrm{E}=\mathrm{hf} \\ & \mathrm{ML}^2 \mathrm{~T}^{-2}=[\mathrm{h}] \times\left[\mathrm{T}^{-1}\right] \\ & {[\mathrm{h}]=\left[\mathrm{ML}^2 \mathrm{~T}^{-1}\right]} \\ & \mathrm{L}=[\mathrm{MVR}]=\left[\mathrm{ML}^2 \mathrm{~T}^{-1}\right] \\ & \mathrm{L}=\frac{\mathrm{nh}}{2 \pi}
\end{aligned}\frac{\mathrm{h}}{2 \pi}$
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This is a previous-year question from JEE Main 2025, covering the Units and Dimensions chapter of Physics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.