Question

You’d like to know the sign (positive or negative) of your piece of charged tape. How might you determine the sign of charge on your tape? Keep in mind that neutral uncharged matter is attracted to both positive and negative charge.

How do you think one would make two OPPOSITELY charged pieces of tape? Describe a process that would allow you to make two pieces of oppositely charged tapes and how you know that they would be oppositely charged.

Answer 1

To do this we need

• a glass rod
• a ebonite rod
• a silk cloth
• a fur cloth
• two wooden blocks

Negatively charging the tape

1. Now let’s ground one end of the tap by taping it to the floor and keep the other end on a wooden block
2. Then rub the glass rod with silk, this will make the glass rod positively charged.
3. Then hold this glass rod near the elevated end of the tape without touching it.
4. this way the negative charges will move towards the elevated end of the tape and the positive charges will move to ground
5. While still holding the glass rod, elevate the grounded end with the help of another wooden rod.
6. now we can move the glass rod away
7. The tape is negatively charged now.

Positively charging the tape

1. Now let’s ground one end of the tap by taping it to the floor and keep the other end on a wooden block
2. Then rub the ebonite rod with fur, this will make the ebonite rod negatively charged.
3. Then hold this ebonite rod near the elevated end of the tape without touching it.
4. this way the positive charges will move towards the elevated end of the tape and the negative charges will move to ground
5. While still holding the ebonite rod, elevate the grounded end with the help of another wooden rod.
6. now we can move the ebonite rod away
7. The tape is positively charged now.

We can see that the first tape deflect the ebonite rod while attract the glass rod

We can also see that the second tape deflect the glass rod and attract the ebonite rod.

This way we can understand they are charged oppositely