Answers

2014-05-12T23:00:31+05:30
As the electric field is radially inward so charge on sphere is negative.
electric field outside due to a conducting sphere is given by 
E = K*Q / r^2          (K = 9*10^9)
1.5*10^3 = 9*10^9*(-Q) / .2^2
on solving we get 
Q = -20 / 3 nc 
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