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Saturday, 31 October

JEE Main 2026 · PhysicsMultiple choiceSingle correctMediumMulti-step

JEE Main 4 April 2026, Shift 1, Physics Q40

Question 40 of 75 in this shift, Physics question 15 of 25, Section A.

A parallel plate air capacitor is connected to a battery. The plates are pulled apart at uniform speed vv. If xx is the separation between the plates at any instant, then the time rate of change of electrostatic energy of the capacitor is proportional to xαx^{\alpha}, where α\alpha is ______.
  1. (1)−2-2Official answer
  2. (2)11
  3. (3)−1-1
  4. (4)22

Official answer

Option 1

NTA final key.

Chapter
Electrostatic Potential and Capacitance
Topic
Parallel Plate Capacitors
Idea tested
Energy Stored in Capacitor

Same idea in other shifts

Asked 2× in all
  1. 24 Jun 2022, Shift 2 · Q45If the charge on a capacitor is increased by 2 C, the energy stored in it increases by 44%. The original charge on the capacitor is (in C)EasySingle correct

Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.