At the centre of a half ring of radius R = 10 cm and linear charge density 4 nC m-1, the potential is x V. The value of x is .
36
Every element of the half ring is at the same distance R from the centre, so V = kQR with Q = ( R).
V = k = 9 109 4 10-9 = 36 V
x = 36
Answer: 36
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