Chapter 20.1, Problem 3SSC

To determine

Whether a pitch ball suspended from an insulating thread is neutral, charged positively or charged negatively.

Explanation of Solution

Introduction:

There are two types of charges. Positive charge and negative charge. Unlike charges attract each other and like charges repel each other.

If you take positively charged particle or object like glass rod near the pitch ballif it is repelled the charge is positiveand if it is attracted pitch ball may havenegative or neutral.

Now bring negatively charged object closer to pitch ball if it repelled then the pitch ball is negatively charged. If it is attracted the pitch ball is neutral.

Conclusion:

The charge on pitch ball is identified by bringing positively and negatively charged object closer to pitch ball.