Solution Found!
(a) Show that V for a spherical shell of radius R, that
Chapter 23, Problem 41E(choose chapter or problem)
(a) Show that V for a spherical shell of radius R, that has charge q distributed uniformly over its surface, is the same as V for a solid conductor with radius R and charge q.
(b) You rub an inflated balloon on the carpet and it acquires a potential that is 1560 V lower than its potential before it became charged. If the charge is uniformly distributed over the surface of the balloon and if the radius of the balloon is 15 cm, what is the net charge on the balloon?
(c) In light of its 1200-V potential difference relative to you, do you think this balloon is dangerous? Explain.
Questions & Answers
QUESTION:
(a) Show that V for a spherical shell of radius R, that has charge q distributed uniformly over its surface, is the same as V for a solid conductor with radius R and charge q.
(b) You rub an inflated balloon on the carpet and it acquires a potential that is 1560 V lower than its potential before it became charged. If the charge is uniformly distributed over the surface of the balloon and if the radius of the balloon is 15 cm, what is the net charge on the balloon?
(c) In light of its 1200-V potential difference relative to you, do you think this balloon is dangerous? Explain.
ANSWER:Solution 41E Step 1 : Consider the electric field outside and inside the shell and use that to deduce the potential. (a) The electric field outside the shell is the same as for a point charge at the center of the shell, so the potential outside the shell is the same as for a point charge : q V = 40 rfor r > R