JEE Main 2019PhysicsElectrostaticsElectric Charges And Coulombs LawmediumMCQ

JEE Main 2019Electrostatics Question with Solution

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

Question

Charge is distributed within a sphere of radius R with a volume charge density where A and a are constants. If Q is the total charge of this charge distribution, the radius R is :

Choose an option

Show full solutionCorrect option: B
Correct answer
B log

Step-by-step explanation

JEE Main 2019 (Online) 9th January Evening Slot Physics - Electrostatics Question 204 English Explanation

Volume of this spherical layer,

dv = (4r2)dr

charge present in this layer,

dq = (4r2 dr)

=

=

  Total charge in the sphere,

Q=

= 4A

= 4A

= 4A

  Q = 2aA

   =

   = 1

   =

  

  R = log

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Electrostatics chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

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