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JEE Main202125 Feb 2021Morning ShiftPhysicsElectrostaticsActual

512 identical drops of mercury are charged to a potential of 2 V each. The drops are joined to form a single drop. The potential of this drop is V in Volt.

Correct answer

128

Step-by-step solution

Q = 512   q   Volume   i =   Volume   f 512 × 4 3 π r 3 = 4 3 π R 3 2 9 r 3 = R 3 R = 8   r 2 = k q r V = k Q R = k 512 q 8 r V = 128   V .

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