Electricity Flashcards
What are circuit diagrams?
a map of electric circuits
What is the purpose of circuit diagrams?
- stylised way of drawing circuit, easier to follow
- study and develop new circuits
What are closed and open circuits?
A closed circuit is a complete circuit and an open circuit has a break in it
What is a series circuit and what happens to bulbs?
- only one pathway for electrons to flow
- if one bulb blows, they all go out
- more bulbs, less glow
What is a parallel circuit and what happens to bulbs?
- several pathways for electrons to flow
- if one bulb blows, the remaining stay on
- all bulbs maintain their glow
Define what a power supply, load and conduction path are?
- the power supply is the electricity source e.g. battery, generator, outlet
- the load is the component that consumes electrical energy and converts it to other forms like heat and light
- the conduction path is the route where current flows through the circuit
current is ________________ to voltage
directly proportional
What is electric current?
the flow of electrons around a circuit
What is current measured in and what is used to measure it?
amperes (amps) are measured by ammeters
The higher the current, the …
- faster an object moves
- increase no. of electrons flowing through circuit per second
Which circuit do you measure current?
- current is the same throughout circuit in series
- current is different in each loop of parallel circuit
What is an electrical circuit?
a closed loop that is the path for the transfer of electrical energy from battery or power point to electrical component.
What does an electrical component do?
converts electrical energy into other forms e.g. light, heat, sound kinetic
What 3 things does a electrical circuit need:
- source of electrical energy aka power supply with positive and negative terminals.
- component to convert electrical energy to other forms of energy aka load
- wires aka conduction path connecting component/s to electrical source to form loop
What two things make circuits safer?
- switches control the flow of energy
- fuses and safety switches break the circuit, cutting supply, when they detect large currents
What is voltage?
- aka as potential difference
- amount of energy or ‘push’ a power supply gives to electrons
What are voltages measured in and what is used to measure it?
volts (V) are measured by voltmeters
As current passes through load, what does voltage do?
drops
Which circuit do you measure voltage?
- in series voltage is shared
- in parallel every loop has same voltage
name voltages given in the following electrical sources: AA battery, car battery, power points in home.
1.5V, 12V and 240V respectively
What is resistance?
- the measure of how easy it is for electricity to pass through a conductor
- a material’s opposition to the flow of electric current
describe what happens in resistance.
the electrons collide with the particles that make up the conductor it is passing through. it obstructs the flow of electrons and causes the no. of electrons passing to decrease. electrons lose their energy from friction experienced during collision which is converted to other forms of energy.
What is resistance measured in?
measured in ohms represented by greek letter omega (basically the libra sign)
Resistance depends on what three things?
wire length: longer the wire, more resistance
wire thickness: thinner the wire, greater the resistance
kind of metal: nichrome provides more resistance
