A bellow conducting sphere has an inner radius of r1 12 cm

A bellow conducting sphere has an inner radius of r_1 = 1.2 cm and an order radius of r_2 = 35 cm. The sphere has a net charge of Q = 2.5 nC. What is the magnitude of the electric field in the cavity at the center of the sphere, in newtons per coulomb? What is the magnitude of the field, in newtons per coulomb, inside the conductor, when r_1

Solution

a)

Electric field inside the sphere will be 0 as all the charges reside on the outer surface

So, by Gauss Law, threre will never be any Gaussian surface inside r < r2 where charge inside it will be non zero.

So, E = 0

b)

E = 0 <-------same explantion as above

c)

For r > r2 ,

the charge on the sphere will act as a point charge at the center of the sphere

So, E = k*q/r^2

So, E = 9*10^9*2.1*10^-9/7.3^2 = 0.355 N/C <-----answer