JEE Main 2015PhysicsUnits and DimensionsEasyMCQ

JEE Main 2015 — Units and Dimensions Question with Solution

JEE Main 2015 (10 Apr Online)

Question

If the capacitance of a nanocapacitor is measured in terms of a unit u,  made by combining the electronic charge e, Bohr radius a0, Planck's constant h and speed of light c then

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Show full solutionCorrect option: A
Correct answer
Au=e2a0hc

Step-by-step explanation

∵     Capacitance C=Q∆V 

Also, hcλ= hca0= Energy. 

∴     C= Q∆V= Q Q∆V Q

∵     W=q∆V    ⇒     Q ∆V= Energy

∴     C= Q2Energy= Q2 a0hc

∴     Capacitance= Q2 a0hc

⇒     u= e2 a0hc

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About this question

This is a previous-year question from JEE Main 2015, 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.