NCERT Solution
Class 12
Physics
Electrostatic Potential and Capacitance
a 4 micro f capacitor is charged by a 200 v suppl...

Question:
A 4 µF capacitor is charged by a 200 V supply. It is then disconnected from the supply, and is connected to another uncharged 2 µF capacitor. How much electrostatic energy of the first capacitor is lost in the form of heat and electromagnetic radiation?

Answer:

Capacitance of a charged capacitor, C₁=4µF = 4 x 10^-6 F

Supply voltage, V₁ = 200 V

Electrostatic energy stored in C₁ is given by,

Capacitance of an uncharged capacitor, C₂=2µF = 2 x 10^-6 F

When C₂ is connected to the circuit, the potential acquired by it is V₂.

According to the conservation of charge, initial charge on capacitor C₁ is equal to the final charge on capacitors, C₁ and C₂.

Electrostatic energy for the combination of two capacitors is given by,

Hence, amount of electrostatic energy lost by capacitor C₁

= E₁ - E₂

= 0.08 - 0.0533 = 0.0267

=2.67 × 10 ^{- 2} J

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Question:
A 4 µF capacitor is charged by a 200 V supply. It is then disconnected from the supply, and is connected to another uncharged 2 µF capacitor. How much electrostatic energy of the first capacitor is lost in the form of heat and electromagnetic radiation?

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Question: A 4 µF capacitor is charged by a 200 V supply. It is then disconnected from the supply, and is connected to another uncharged 2 µF capacitor. How much electrostatic energy of the first capacitor is lost in the form of heat and electromagnetic radiation?

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Question:
A 4 µF capacitor is charged by a 200 V supply. It is then disconnected from the supply, and is connected to another uncharged 2 µF capacitor. How much electrostatic energy of the first capacitor is lost in the form of heat and electromagnetic radiation?