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Physics · Work, Power & Energy

JEE Main 2025 — 2 April, Morning Shift — Question 47

The battery of a mobile phone is rated as 4.2 V , 5800 mAh . How much energy is stored in it when fully charged?

  1. Option A:

    43.8 kJ

  2. Option B:

    48.7 kJ

  3. Option C:

    87.7 kJ

    Correct
  4. Option D:

    24.4 kJ

Answer: C

Step-by-step solution

Energy stored in battery =(mAh)×V×36001000=\frac{(\mathrm{mAh}) \times \mathrm{V} \times 3600}{1000}

=5800×4.2×36001000=87.7 kJ\begin{aligned} & =\frac{5800 \times 4.2 \times 3600}{1000} & =87.7 \mathrm{~kJ} \end{aligned}

Answer key and solution verified before publishing.

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Exam
JEE Main 2025
Paper
2 April, Morning Shift
Subject
Physics
Chapter
Work, Power & Energy
Topic
Power
The battery of a mobile phone is rated as 4.2 V , 5800 mAh . How much… | JEE Main 2025 PYQ with Solution · DhiX AI