JEE Main 2019PhysicsCurrent ElectricityResistance And ResistivitymediumMCQ

JEE Main 2019Current Electricity Question with Solution

From: JEE Main 2019 (Online) 9th April Evening Slot

Question

In a conductor, if the number of conduction electrons per unit volume is 8.5 × 1028 m–3 and mean free time is 25ƒs (femto second), it's approximate resistivity is :-
(me = 9.1 × 10–31 kg)

Choose an option

Show full solutionCorrect option: A
Correct answer
A10–8 m

Step-by-step explanation



= 3.34 × 10–8 m

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About this question

This is a previous-year question from JEE Main 2019, covering the Current Electricity 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.