Electricity Flashcards
Define charge…
The movement of energy from one place to another
Define static electricity…
- The build-up of electric charge on a surface
How does static electricity occur, and what happens when it does occur?
- This build-up commonly occurs as a result of the surface being rubbed against another surface.
- Electrons (-) have been rubbed off one surface (charging it positive) and have transferred to the other surface (charging it negative).
What happens to static charge after a while?
- Static charge usually leaks away after some time into its surroundings, including the air around it, returning materials to their original neutral state.
Define Current…
- When electrons move along a wire, this movement of charge is called an electric current.
- If the electrons don’t move, no energy is received by the light globe or appliance, so nothing happens – it stays ‘off’.
What is Voltage?
- Voltage is a measure of the amount of energy; supplied to the charges by the voltage source, used by the charges as they pass through a component.
How do you determine if something is overall negative or positive?
- If something is positive, it will have more positive charges than negative
- If something is negatively charged, then it will have more negative charges than positive
What is it called when something has equal positive to negative charges?
- It is neutrally charged
What is a conductor?
- A conductor is an object or type of material that allows the flow of an electrical current through it. These often include types of metals
Name types of conducting materials…
- Copper, aluminium, silver, gold
What is an insulator?
- A material in which very little electric current will flow through under the influence of an electric field
- A material that responds with very high resistance to the flow of electrical current or totally resists electric current is called an insulating material
Name types of insulating materials…
- Types of insulating materials include PVC, glass and rubber
What is the subatomic particle responsible for the production of current?
- Electrons are responsible for circuits
What does an electrical circuit NEED?
- An electric circuit needs: an energy source, an energy user and wires to connect everything and complete the circuit.
A circuit will only operate if it is…..
- Complete. A circuit must be complete for it to operate
Other reasons that a circuit may not work include…
- Negative to negative
- A light globe is “blown” (when connected in series)
- Circuit is not complete
A circuit may include…
- Something to control the current (switch)
- Something to modify the size of the current (resistors)
- Something to store the current temporarily (capacitors)
How are household circuits connected?
- Household circuits have combinations of series and parallel circuits
If a Circuit is connected in Parallel, then…
- Each energy user has its own connection to the power source. This means that each power user gets the full amount of energy (voltage) from the power source
If a circuit is connected in Series, then…
- All of the energy users are connected in a “loop”, and they share the power source. This means that the more power users connected to the circuit, the less power that each will get. For example, if the power source is 9 Volts, and there are three light bulbs, each light bulb will only get 3 Volts of energy.
Define resistance…
- Resistance is the measure of difficulty to pass an electric current through a conductor such as electrical wiring.
