Lesson 3 - Current

Question 1

Describe how static charge is built up and then released. Take a balloon and a wall as an example.

Answer 1

When the 2 surfaces rub together, they create friction. Because of the friction, a charge is formed. The charge is transferred from the are on the wall to the balloon. Then when you rub it in your hair, it transfers from your balloon to your hair. Not all charges are transferred though - some particles are left behind on the balloon and on the wall.

Summary - Friction between 2 insulators and then they touch a conductor. The atoms lose electrons.

Question 2

What is ‘current’?

Answer 2

Current is the amount of charge flowing per second.

Question 3

What is an electric circuit?

Answer 3

An electric circuit is a loop of wire that is connected end-to-end with a an energy source, such as a cell or a battery.

Question 4

When a battery is connected in a circuit, what happens inside the wires?

Answer 4

The electrons in all parts of the wires within this circuit move in the same direction, at the same time and at the same rate - this movement is current.

Question 5

What will happen if there is an insulator in your circuit?

Answer 5

If there is an insulator in your circuit, then the electricity will not be able to flow properly and the circuit will not work.

Question 6

Describe the symbol for an ammeter

Answer 6

A circle with the letter A inside it, with a line going behind it.

Question 7

Describe the symbol for a fuse

Answer 7

A fuse is a rectangular box with a line going through it.

Question 8

Describe the symbol for a variable resistor?

Answer 8

A variable resistor is a rectangle with a line going behind it, and an arrow pointing diagonally up.