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Question
Two charged particles, with equal charges of 2.0 × 10−5 C, are brought from infinity to within a separation of 10 cm. Find the increase in the electric potential energy during the process
Solution
Magnitude of charges, q1 = q2 = 2 × 10−5 C
Initial potential energy = 0
Each is brought from infinity to within a separation of 10 cm.
That is, r = 10 × 10−2 m
So, increase in potential energy = final potential energy − initial potential energy.
That is, increase in potential energy,
\[∆ \text{U} = \frac{1}{4\pi \epsilon_0}\frac{q_1 q_2}{r}\]
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