JEE Main 2024PhysicsElectrostaticsHardNumerical

JEE Main 2024 — Electrostatics Question with Solution

JEE Main 2024 (30 Jan Shift 2)

Question

Two identical charged spheres are suspended by strings of equal lengths. The string make an angle of 37° with each other. When suspended in a liquid of density 0.7 g cm-3, the angle remains same. If density of material of the sphere is 1.4 g cm-3, the dielectric constant of the liquid is _____ tan37°=34

Enter your answer

Show full solutionCorrect answer: 2
Correct answer
2

Step-by-step explanation

For first case:

Tcosθ=mg and 

Tsinθ=Fe

Therefore, tanθ=Femg

tanθ=FeρBVg....(i)

For second case:

tanθ=FekρBVg-ρLVg.....(ii) 

From Eq. (i) & (ii), we get

ρBVg=ρB-ρLkVg

⇒1.4 = 0.7 k 

⇒k = 2 

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 2024, 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.