Important Things For Topic 3.1!!

Question 1

How does a polythene rod become negatively charged?

Answer 1

Rub a polythene rod with a cloth.
Electrons are transferred from the cloth to the rod, producing a net negative charge, and leaving the cloth positively charged.

Question 2

What happens if you bring the negatively charged rod to pieces of paper?

Answer 2

The negatively charged rod repels the electrons in the pieces of paper, so the tops of the pieces of paper become positively charged. They are attracted to the rod.

Question 3

Why are there two separate regions in clouds when they become charged?

Answer 3

Before the cloud was charged it was neutral so there must be two regions of charge in the cloud, one positive and one negative.

Question 4

How do pepper grains form a field?

Answer 4

Electrons in the pepper grain move away from the positive rod and towards the negative rod.
There is a field around the pepper grain because one end is negative and one end is positive.
This distorts the field, so the pepper grains line up so that the field lines are as straight as possible.

Question 5

How does a balloon make water “bend”?

Answer 5

balloon is negatively charged
(1)
electrons in water are repelled (1)
opposite charges / positive and negative attract (1)

Question 6

How much charge does one electron have?

Answer 6

-1.6 x 10 to the power of 19 C

Question 7

How many electrons are needed for one coulomb of charge?

Answer 7

6.25 x 10 to power of 18 electrons = 1 Coulomb of Charge.