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JEE Main20252 Apr 2025Morning ShiftPhysicsCurrent ElectricityActual

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

Options

  1. A43.8 kJ
  2. B48.7 kJ
  3. C87.7 kJ
  4. D24.4 kJ

Correct answer

C. 87.7 kJ

Step-by-step solution

Given V =4.2 volt Energy supplied by battery = vq =4.2 5800 3600 10⁻³ ~J =87.696 ~kJ Energy stored in the battery when fully charged =87.696 ~kJ 87.7 ~kJ

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