Question

True or Flase, preferably explain the reasoning behind the answer

a)The electric field inside the solid metal sphere is never zero

b)If the solid sphere is an insulator (instead of metal) with net charge Q, the charges are wherever they were placed, and cannot move around.

c) If the solid sphere is an insulator (instead of metal) with net charge Q, the electric field for r >> R would be the same as that of a conductor with the same shape and charge.

d)The net charge on the inside of the solid metal sphere is neutral.

e)The electric field for the metal sphere at r << R will be the same as the field of a point charge, Q, at the origin

f)The electric field near the metal surface on the outside is parallel to the surface.

Answer 1

a) False

Explanation : for a sollid sphere net charge always resides on its surface.so, net charge inside is zero.

According to gauss law

integral E*ds = Qin/epsilon

intergral E.ds = 0

==> E = 0

b) True
Explanation: the charge remains the same place wherever we place it.

c) True
Explanation :
According to gauss law

integral E*ds = Qin/epsilon

E.4*pi*r^2 = Qin/epsilon

for both spheres, Qin = Q

E = (1/4*pi*epsilon)*Q/r^2


d) True
Explanation : net charge always resides on its surface

e) False
Explanation :
Explanation :
According to gauss law

integral E*ds = Qin/epsilon

E.4*pi*r^2 = Qin/epsilon

for conducting and non conducting spheres Qin is not same. so, E is not same in side the sphere.

Note: for metal sphere inside no net charge

f) False
Explanation : electic filed is radially outward or inward.

for +ve charged sphere E is radially outward

for -ve charged sphere E is radially inward