# Figure shows a closed dotted surface which intersects a conducting uncharged sphere . If a +ve charge is placed at the point P, the flux of the electric field through the closed surface

$(a)\;will\;remain\;zero\qquad(b)\;will\;become\;+ve\qquad(c)\;will\;become\;-ve\qquad(d)\;data\;insufficient$

Answer : (c) will become -ve
Explanation :
If a +ve charge is placed at the point P then a -ve charge will induced onthe surface near to P
And the flux through the closed dotted surface is
$\phi=\large\frac{q_{inc}}{\in_{0}}$
$q_{inc}\;$ i.e. charge enclosed in the closed dotted surface is _ve and hence the flux through this surface will become -ve when a +ve charge is placed at P .
edited Feb 19, 2014 by yamini.v