Net electrostatic energy for the system U=K[aq2+aQq+a2Qq]=0 
⇒q=−Q[1+21]⇒Q=2+1−q2
JEE Main 2019 — Physics Electromagnetism
Three charges Q,+y and +q are placed at the vertices of a right-angle isosceles triangle as shown below. The net electrostatic energy of the configuration is zero, if the value of Q is 
Held on 11 Jan 2019 · Verified 6 Jul 2026.
+q
2+1−2q
1+2−q
−2q
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