Question

The figure shows a hallow metal sphere with inner radius 2.10 cm and outer radius 13.1 cm and a point charge at the center. The inner surface of the hollow sphere has a total charge of 8.70 nC and the outer surface has a total charge of-22-9 nc Calculate the value of the charge at the center of the metal sphere. Answer Calculate the magn tude electric field a distance 24.0 cm from the center of the sphere Answer: fthe electric field? O outward Inward Question 2 A charge of uniform linear density 2.64 nC/m is distributed along a long, thin, nonconducting rod. The rod is coaxial with a long canducting cylindrical shell with an inner radius of 7.26 cm and an outer radius of 11.7 cm. If the net charge on the shell is zero, what is the surface charge density an the inner surface of the shell What is the surface charge density on the outer surface of the shell?

Answer 1

Question 1

(a)

charge at the centrer of the metal sphere will be equal to negative of inner surface charge of the hollow sphere

q = - 8.70 nC

b)

electrical field at a distance r = 24 cm will only due to outer surface charge of hollow sphere

E = kQ/r^2

so magnitude of electric field is E = [( 9*10⁹)*(22.9*10^-9)] / (0.24)² = 3578.12 N/C

c)

direction of electrical field is INWARD because outer sphere charge is negative.

Question 2

$\sigma$_in = -$\lambda$/2*pi*r_in = 2.64*10^-9 /2*3.14*0.0726

$\sigma$_in = - 5.79*10^-9 C

$\sigma$_out =  $\lambda$ /2*pi*r_out = 2.64*10^-9 /2*3.14*0.117 = 3.59*10^-9 C