A point charge is surrounded symmetrically by six identical charges at distance $r$ as shown in the figure. How much work is done by the forces of electrostatic repulsion when the point charge $q$ at the centre is removed at infinity
A
Zero
B$6{q^2}/4\pi {\varepsilon _0}r$
C${q^2}/4\pi {\varepsilon _0}r$
D$12{q^2}/4\pi {\varepsilon _0}r$
Medium
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B$6{q^2}/4\pi {\varepsilon _0}r$
b (b) Total potential at the centre $V = \frac{{6q}}{{4\pi {\varepsilon _0}r}}$
Required work done $ = q.V = \frac{{6{q^2}}}{{4\pi {\varepsilon _0}r}}$
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