Physics · Capacitors and R-C Circuits

JEE Main 2025 — 24 January, Morning Shift — Question 47

Consider a parallel plate capacitor of area A (of each plate) and separation 'd' between the plates. If E is the electric field and ε0\varepsilon_{0} is the permittivity of free space between the plates, then potential energy stored in the capacitor is :-

  1. Option A:

    12ε0E2Ad\frac{1}{2} \varepsilon_{0} E^{2} \mathrm{Ad}

    Correct
  2. Option B:

    34ε0E2Ad\frac{3}{4} \varepsilon_{0} \mathrm{E}^{2} \mathrm{Ad}

  3. Option C:

    14ε0E2Ad\frac{1}{4} \varepsilon_{0} E^{2} \mathrm{Ad}

  4. Option D:

    ε0E2Ad\varepsilon_{0} E^{2} A d

Answer: A

Step-by-step solution

UV=12ϵ0E2\frac{U}{V}=\frac{1}{2} \epsilon_{0} E^{2}

U=12ϵ0E2 V\mathrm{U}=\frac{1}{2} \epsilon_{0} \mathrm{E}^{2} \mathrm{~V}

=12∈0E2(Ad)=\frac{1}{2} \in_{0} \mathrm{E}^{2}(\mathrm{Ad})

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Subject
Physics
Chapter
Capacitors and R-C Circuits
Topic
Force Between Plates and Potential Energy Stored
Consider a parallel plate capacitor of area A (of each plate) and… | JEE Main 2025 PYQ with Solution · DhiX AI