electric potential/field

2011-09-25 6:41 am

Comment on the correctness of the following statements. Give examples, if any, to support your argument.

a) An earthed object must be neutral

b) A negatively charged object must be at a negatively potential(i.e. V<0)

c) The electric potential of an uncharged object can be positive

d) The electric potential inside an insulated conductor is the same everywhere

e) For a conductor in electrostatic, the electric field strength inside is zero, even though it is charged

f) Electric field strength can vary drastically from point to point, but the electric potential always varies continuously.

g) The electric field on the surface of an uncharged conductor is always zero

回答 (1)

天同

2011-09-25 8:22 am

✔ 最佳答案

(a) False. An earthed object is only at zero potential. It could carries charges, e.g. another charged object is placed nearby.

(b) False. If placed near another object that carries large amount of +ve charge (as compared with the -ve charge carried by the object), the -ve charged object would have +ve potential.

(c) False, if there is the object alone. But if an object has no excessive charge, its potential may not necessarily be zero.

(d) True.

(e) True.

(f) What do you mean by "drastically"? Please specify.

(g) True, if there is only the uncharged conductor alone.

👍 0 👎 0