Question

What is electroscope? Explain how it works.

Answer 1

1. An electroscope is a scientific instrument used to detect the presence of electric charge on a body.

2. An electroscope is made out of conducting materials, generally metal.

3. It works on the principle that like charges repel each other.

4. In a simple electroscope two metal sheets are hung in contact with each other.

5. They are connected to a metal rod that extends upwards and ends in a knob at the end.
   
   Movement of charges in electroscope

6. If you bring a charged object near the knob, electrons will either move out of it or into it.

7. This will result in charges on the metal leaves inside the electroscope.

8. If a negatively charged object is brought near the top knob of the electroscope, it causes free electrons in the electroscope to move down into the leaves, leaving the top positive.

9. Since both the leaves have a negative charge, they repel each other and move apart.

10. If a positive object is brought near the top knob of the electroscope, the free electrons in the electroscope start to move up towards the knob.

11. This means that the bottom has a net positive charge. The leaves will spread apart again. Explain series and parallel circuits.