A hollow conducting sphere with an outer radius of 0.295 m and an inner radius of 0.200 m has a uniform surface charge density of 6.37 10 6 C m2 A charge of 0.370 µC is now introduced into the cavity inside the sphere a What is the new charge density on the outside of the sphere b Calculate the strength of the electric field just outside the sphere

a.

b.

Explanation:

#Apply  surface charge density, electric field, and Gauss law to solve:

a. Surface charge density is defined as charge per area denoted as

, and the strength of the electric field outside the sphere

Using Gauss Law, total electric flux out of a closed surface is equal to the total charge enclosed divided by the permittivity.

 #surface charge outside sphere.

Hence, the new charge density on the outside of the sphere is

b. The strength of the electric field just outside the sphere is calculated as:

From a above, we know the new surface charge to be ,

Hence, the strength of the electric field just outside the sphere is

what type of charge does it have? negative