Transmitting electricity Flashcards
what is the purpose of a transformed
to change the potential difference of an alternating current
describe what a transformer looks like
an iron core with 2 coils on either side
how does a transformer work
when current flows through the primary coil it produces a changing magnetic field in the iron core, the magnetic field will induce an alternating PD across the secondary coil.
what effects the PD change made by a transformer
the number of coils on the primary and secondary sections
what is the efficiency of a transformer
100%
As potential difference increases in a transformer the current…
decreases
what are the 2 types of transformers
step up
step down
what is the national grid
a system of wires that transmit electricity from power stations to where it is needed
what are the 2 parts of the national grid
wire
transformers
why are transformers used in the national grid
to ensure that transmission is efficient and as little energy is lost as heat
what are 2 benefits of using a high voltage when transmitting energy through wires
more efficient as less energy is lost
thinner wires can be used
what voltage is electricity transported at
132Kv
why are step-down transformers used
to decrease the voltage top a voltage that is safer for our homes
what is the formula for power that uses current
power = current squared * resistance
if the current is double how much more power would be wasted
4 times more
