E-Activity 15

1. When you rub two different materials together, they become charged. Why?
2. What type of electrical charge does each electron carry?
3. Copy and complete the sentence.
When you rub a piece of polythene with a cloth, you make electrons move from the ____________ to the _______________.
4. Explain the following, as fully as you can.
(a) The polythene ends up with a negative charge.
(b) The cloth ends up with a positive charge.
5. The negative charge on the polythene is exactly equal to the positive charge on the cloth. Why is this?
6. (a) What type of charge do you get on a cloth when you rub apiece of acetate with it?
(b) What happens to the electrons as you rub the acetate with a cloth?
7. Copy and complete the sentence.
When you peel different materials apart, one of them becomes__________ charged and the other becomes _____________ charged.
8. When you peel some sticky tape from a roll, it often tends to go back on again. Explain, as fully as you can, why it does this.