Question

A charge 4q is at a distance r from a charge –q. Compare the number of electric field lines leaving the charge 4q with the number entering the charge –q. Where do the extra lines beginning on 4q end?

Answer 1

Answer:

A charge +4q is placed a distance of r from a charge -q. Compare the number of electric field lines leaving +4q with the number entering -q. Please explain your answer for full credit.

A) There are 2 times as many leaving +4q.

B) There are 4 times as many entering +4q.

C) There are 4 times as many leaving +4q.

D) There are 16 times as many leaving +4q.

E = kq / r^2

For +4q, E1 = 4kq / r^2

For -q, E2 = -kq / r^2

so  correct option is C

Explanation:

B and C are not the same, because in B, electric field lines are entering into +4q and in C electric field lines are leaving from +4q.  Since +ve charge are source so C is the correct answer