Two identical pith balls supported by insulating threads hang side by side and close together, as shown below. One is positively charged; the other is neutral. We can conclude that
A) all field lines leaving the positively charged pith ball end on the neutral pith ball.
B) some of the field lines leaving the positively charged pith ball end on the neutral pith ball.
C) none of the field lines leaving the positively charged pith ball end on the neutral pith ball.
D) positive charge is transferred along the field lines until both balls have equal charges.
E) positive charge is transferred along the field lines until both balls hang along vertical lines.

Question

Two identical pith balls supported by insulating threads hang side by side and close together, as shown below.  One is positively charged; the other is neutral. We can conclude that
A) all field lines leaving the positively charged pith ball end on the neutral pith ball. 
B) some of the field lines leaving the positively charged pith ball end on the neutral pith ball. 
C) none of the field lines leaving the positively charged pith ball end on the neutral pith ball. 
D) positive charge is transferred along the field lines until both balls have equal charges. 
E) positive charge is transferred along the field lines until both balls hang along vertical lines.

Quizplus · Accepted Answer

The positively charged pith ball will create an electric field which will induce a separation of charge on the neutral pith ball, causing some negative charge to be attracted towards the positively charged pith ball and some positive charge to be repelled towards the far end of the neutral pith ball. As a result, some of the field lines leaving the positively charged pith ball will end on the neutral pith ball. However, not all field lines will end on the neutral pith ball since there is no conducting path for the charges to flow along the insulating threads.

Two Identical Pith Balls Supported by Insulating Threads Hang Side