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An electron rotates in a circle around a nucleus having positive charge Ze. Correct relation between total energy (E) of electron to its potential energy (U) is :
(3) 2E = U
mv2r = kZe2r2 K = 12mv2 = kZe22r
U = - kZe2r K = - U2
E = K + U = - U2 + U = U2
2E = U
Answer: (3)
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