Question

charging an insulator (1 a non - metal) insulators. we take as an example a long insulating rod suspended by insulating wires. assume that the rod is initially electrically neutral. for convenience, we will refer to the left end of the rod as end a, and the right end of the rod as end b (figure 1). in the answer options for this problem, \weakly attracted/repelled\ means \attracted/repelled with a force of magnitude similar to that which would exist between two balls, one of which is charged, and the other acquires a small induced charge\. an attractive/repulsive force greater than this should be classified as \strongly attracted/repelled\. figure a small metal ball is given a negative charge, then brought near (i.e., within a few millimeters) to end a of the rod. what happens to end a of the rod when the ball approaches it closely this first time? select the expected behavior. view available hint(s) ∘ strongly repelled ∘ strongly attracted ∘ weakly attracted ∘ weakly repelled ∘ neither attracted nor repelled submit now consider what happens when the small metal ball is repeatedly given a negative charge and then brought into contact with end a of the rod part b

Explanation:

When a negatively charged metal ball is brought near an electrically neutral insulating rod (end A), charge induction occurs. The negative charge on the ball induces a slight separation of charges in the insulator: positive charges in the rod are attracted towards the negative ball (near end A), and negative charges are repelled away. Since the rod is an insulator, the induced charge separation is small (not a full transfer or strong polarization like in a conductor). The force between the induced small positive charge at end A and the negative ball is attractive, and because the induced charge is small, the attraction is weak (matching the "weakly attracted" definition given: force similar to that between a charged ball and another with a small induced charge). "Strongly" would imply a larger charge interaction, and repulsion/neutrality don't fit here as the induced charge near A is positive (attracted to negative ball).

Answer:

C. weakly attracted