Electrical Circuits Flashcards
what is a circuit?
a complete circular path that electricity flows through.
This is fulfilled by the uses of components such as the battery, which produces current.
complete circuit…
all the components (parts) in the circuit are connected correctly and there are no gaps, so current can flow
incomplete circuit…
when there is a gap in the circuit so current cannot flow
the gap could be caused by a component not being connected properly, a bulb breaking, a wire being cut or a switch being open.
what is a series circuit?
a complete circuit which only has one route for the current to flow through, so all the charge flows through every component.
what is a parallel circuit?
a complete circuit which has multiple routes for the current to flow through.
this means that only some of the charge will go through each route
what are electrons?
Tiny negatively charged particles found in all atoms.
Electrons carry a very small electrical charge.
It is these electrons which transfer the energy around the circuit.
what is resistance?
This is ‘how difficult’ it is for electrons to pass through a component or wire.
It is measured in Ohms.
The more difficult it is the higher the resistance and the lower the current.
If the resistance is high, the electrons will be forced to transfer more of their energy, causing the wire or component to heat up
Amperes… (A)
unit for current.
For example, we could say that the current is 2.5 Amperes or 2.5A for short
voltage/potential difference… (V)
amount of energy transferred by each charge (remember one charge is many electrons)
for example, if the voltage is 2 Volts, each charge is transferring 2 Joules of energy
what is current?
how much charge (electrons which make up a charge) passes any point in the circuit per second.
A charge is about 16,000,000,000,000,000,000 electrons
wire…
made of metal which is a good conductor of electricity (usually copper)
a wire is thin and long and connects components together in the circuit.
bulb…
electrical component which transfers energy from a store of energy (often a battery) to the surrounding through the emitting of light and heat
cell…
store of chemical energy
battery…
two or more cells.
current produced from the positive side of the battery and comes back to the negative side
switch…
allows the circuit to be turned on and off (can be towards a component in a parallel circuit) by making it COMPLETE or INCOMPLETE
ammeter…
component which measures the current in a circuit.
Must be connected in series
voltmeter…
component which measures the voltage in across a component or components.
It must be connected in parallel
what will happen to a series circuit if a bulb breaks?
if a bulb breaks (or a component is disconnected), the circuit is broken and leaves a gap in the circuit which stops the current passing through along with the components.
This is now known as an incomplete circuit.
Series circuits are useful if you want a warning that one of the components in the circuit has failed. They also use less wiring than parallel circuits.
what will happen to a parallel circuit if a bulb breaks?
if a lamp breaks or a component is disconnected from one parallel wire, only that branch is affected but all the components on different branches keep working.
Uses more wiring than a series circuit.
how to tell if a component will be turned on due to different switches?
an electronic switch controls the flow of current in a circuit and is used to switch a circuit or a component on or off.
All the switches in a series circuit must be closed for the current to flow, therefore function.
If a switch is open on an individual branch in a parallel circuit, that branch will not work but all the other branches will still function as current is split on each branch and isn’t correlated, unlike a series circuit where current is the same all throughout the circuit.
A switch can be aimed towards a component to be turned on and off depending on its state (opened or closed)
what is a motor and how does it work?
An electric motor is a rotating device used in a circuit to convert electricity into mechanical energy which is a renewable source of energy to adequately produce power or convert energy.
They operate using principles of electromagnetism, which shows that a force is applied when an electric current is present in a magnetic field.
This force creates a torque on a loop of wire present in the magnetic field, which causes the motor to spin and perform useful work.
direction of current?
current produced from the positive side of the battery and comes back to the negative side
