# Find charge inner/hollow sphere

## Homework Statement

A hollow conducting sphere with an inner radius of 5 cm and an outer radius of 6 cm contains a smaller sphere of radius 3 cm, located symmetrically inside the hollow sphere. The electric field strength at 4 cm from the center is measured to be 2400 N/C pointing inward. The electric field strength at 20 cm from the center is determined at 300 N/C pointing away from the spheres. Use this information to determine: a. the charge on the inner sphere b. the charge on the hollow sphere

## The Attempt at a Solution

I know I have to use the gauss's law but I am not quite sure how to do it

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## Homework Statement

A hollow conducting sphere with an inner radius of 5 cm and an outer radius of 6 cm contains a smaller sphere of radius 3 cm, located symmetrically inside the hollow sphere. The electric field strength at 4 cm from the center is measured to be 2400 N/C pointing inward. The electric field strength at 20 cm from the center is determined at 300 N/C pointing away from the spheres. Use this information to determine: a. the charge on the inner sphere b. the charge on the hollow sphere

## The Attempt at a Solution

I know I have to use the gauss's law but I am not quite sure how to do it
You have to show some attempt at solving the problem. What does Gauss' Law state?

Consider first a gaussian surface of radius ##r## cm with ##3\lt r\lt 5##, and try to apply gauss's law. Also note that if ##Q## be the charge of the inner sphere, the inner surface of the spherical shell must have charge ##-Q##.

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