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Three point charges Q , + q and + q are placed at the vertices of a right-angled isosceles triangle as shown in the figure. If the net electrostatic energy of the configuration is zero, find the value of Q q is [ Take 2 = 1 .4 ]

Correct answer

-0.6

Step-by-step solution

Net electrostatic energy of the configuration will be U = K [ q · q a + Q · q 2 a + Q · q a ]   Here, K = 1 4 π ε 0 Putting U  = 0 we get, Q q = - 2 2 + 2 × 2 - 2 2 - 2 = 4 - 2 2 2 = - 2 - 2 = - 0 . 6

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