Electricity Flashcards
Learn about the forces at work in your everyday lives
What is an atom?
All substances are made up of atoms, which are the smallest indivisible particles that make up matter.
What three things are atoms made up of?
Protons, neutrons and electrons.
What charge do protons have?
Positive charge.
What charge do electrons have?
Negative charge.
What charge do neutrons have?
Neutrons have no overall charge.
What overall charge does an atom have?
It normally has no overall charge because the protons cancel out the electrons.
What is the centre of an atom called?
The nucleus.
What is in the nucleus?
The protons and neutrons.
What overall charge does the nucleus alone have?
Positive
How many electrons are there in relation to protons?
There are the same amount of protons and electrons.
What is electrical charge?
A flow of Electrons
What do you use an ammeter for?
To measure electrical current.
What is electrical current?
How many electrons per second go through the circuit
What do you use a voltmeter for?
To measure voltage and potential difference.
What is potential difference?
How much energy a component or components use up.
What is voltage?
How much energy each electron carries.
What are the 5 rules of drawing circuit diagrams?
- Use a ruler and a sharp pencil
- Don’t draw a component in the corner
- Always make sure the component is actually connected into the circuit by the wires
- Draw large clear diagrams
- Draw them as a square or rectangle not a trapezium or circle
What is static electricity?
Static electricity is a build-up of electrical charge on an object. Some of the electrons are transferred across by friction.
What happens when OPPOSITE charges are together?
They attract to one another.
What happens when SIMILAR charges are together?
They repel each other.
What does a battery do?
Provides protons and electrons for electricity. It’s a store of chemical energy.
How is a battery drawn?
As a small vertical line next to a slightly larger horizontal line.
What does a wire do?
It Conducts electricity and connects a circuit’s components.
How is a wire drawn?
As a straight line.
What does a switch do?
Breaks or connects a circuit. E.g. a light switch lets power either flow or not flow to the lights.
How is a closed switch drawn?
Two small circles connect by a horizontal line.
How is an open switch drawn?
Two small circles with a diagonal line going from one to just above the other one.
What does a voltmeter do?
It measures a circuit or component’s voltage or potential difference.
How do you draw a voltmeter?
A circle with a V in it.
What does an ammeter do?
It measures the electrical current (in amps) flowing through a circuit.
How is an ammeter drawn?
It is a circle with an A in it.
What does a resistor do?
to reduce the current flow and to lower the voltage in any particular portion of the circuit.
What does a variable resistor do?
It allows you to reduce the current flow and to lower the voltage in any particular portion of the circuit, and change it.
What is an electromagnet?
A metal that has been magnetised by copper coils and the electrical current flowing through the coils.
