Question

Explain the phenomenon of induction that was studied in this activity (bringing a negatively charged plastic rod near an uncharged non-metal-coated styrofoam ball that is hanging freely and an uncharged metal-coated styrofoam ball that is hanging). For example, explain how a metal conductor such as a hanging ball of aluminum foil can be attarcted to a charged insulator even though the ball of foil has no net charge so that is is electrically neutral. Can two metal balls with no net charge attract each other? Explain. Can the process of induction cause a neutral conductor to be repelled from a charged insulator? Explain.

Thank you very much :)

Answer 1

When you bring a negativelyc charged rod near an uncharged non metal coated styroform induction of charge will not take place as styroform is a good insulator and in order to charge it, you need to do it through conduction, but rubbing the rod over the surface of it.

But when you bring the same negatively charged rod near to a metal coated styrofoam ball, the charges will be induced over the surface of the metal coating, the amount of charge induced will be exactly equal and apposite to that of the rod.

Now when the ball has negative charge and the rod has positive charge they will attract each other as unlike charges attract each other while like repels.

For electrical attraction, the balls needs to have some charge then only they will be attracted to each other. If the system has net negative charge to be zero, the other implication is that one may have positive and the other may be same amount of negative so the net charge is zero. Such system will definately have a net force of attraction.

The process of induction can not cause the neutral conductor to be repelled. Since because of indcution, an apposite charge gets induced and apposite charges always attract each other. Hence, they will get attracted to each other.