An uncharged metal sphere, A, is on an insulated base. A second sphere, B, of the same shape, size and material carrying a charge +Q is brought close to but not touching with sphere A. (a) Describe what happens to charges on spheres A and B as they are brought close together but not touching. (b) If we now remove sphere B and place it far away, what is the charge on sphere A? (c) How is this charge (if any) distributed?

a) when we approach sphere B with a positive car Q, it attracts negative charges from sphere A

b) phere A with a charge equal to zero

c) The charges are not distributed since there is no physical contact

Explanation:

a) Electric charges are neither created nor destroyed, they are only distributed, when we approach sphere B with a positive car Q, it attracts negative charges from sphere A in such a way that while the two spheres are close, each one has a charge + Q / 2.

b) when sphere B moves away, it no longer attracts negative charges from sphere A, so they move away from each other and neutralize themselves with positive charges, leaving sphere A with a charge equal to zero

c) The charges are not distributed since there is no physical contact between the two spheres, only a charge is induced when they are close, but when moving away each one is left with its initial charge

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2