Electric current | Exit Quiz | Oak National Academy

Which statement correctly describes the terminals of a battery?

• A battery has one positive terminal and one negative terminal.

• A battery has two positive terminals.

• A battery has two negative terminals.

• A battery has a neutral terminal and either a positive or a negative terminal.

Answer explanation

A battery will have a positive terminal and a negative terminal.

What is inside a battery that pushes the electric charges round a circuit?

• small magnets

• mini-pumps

• microscopic motors

• chemicals that react

Answer explanation

Chemical reactions take place inside a battery which cause a current to flow when the battery is connected to a circuit.

What is the name of the moving charges that carry electric current through a metal wire?

• protons

• electrons

• magnetrons

• neutrons

Answer explanation

Electrons are the charges that move in a metal wire.

What is the normal speed of electrons flowing through a metal wire?

• a few millimetres per second

• a few metres per second

• a few kilometres per second

• a few million metres per second

Answer explanation

The typical speed of electrons flowing through a wire is a few millimetres per second.

Which objects can be used to make a simple battery?

• two pieces of the same metal, liquid oil and some wires

• two pieces of the same metal, a weak acid solution and some wires

• two different metals, liquid oil and some wires

• two different metals, a weak acid solution and some wires

Answer explanation

A battery can be made using two different metals that will react in a weak acid (or alkali) solution. Wires are needed to complete a circuit.

Which two of these objects have free electrons that can carry an electric current?

• plastic ruler

• copper wires

• air in the room

• steel paperclips

• wooden pencil

Answer explanation

The two things that have free electrons that can transmit electricity are copper wires and steel paperclips. They are metal conductors.