Physics Notes Ch.1 February Test Y3
1.1
● The production of energy happens in a power station
● H ow does the production of electricity happen then?
1. Coolant water enters theboiler
2. In the boiler, the water is vapourized under a veryhigh pressure
3. The water, high pressure water vapour enters the turbine, in
which the spinning motion happens (with a sort of rod)
4. The spinning water vapour enters the generator, in which with
the spinning “rod”, energy of movement is turned into electrical
energy
5. The unnecessary water vapour from the turbine goes into the
condenserwhere it is cooled down again
6. The water vapour from thegeneratorentersthetransformer,in
which a magnet is magnetized and demagnetized by soft iron on
coil. Electricity is created!
● P = E over t
P is power inwatts.WattsisJ\s.powermeanshowmuchenergyis
produced in a second
E is energy in J
t is time in seconds
● E = P times t
, t = E over P
●
● Remember: energy doesn't appear\disappear, or get created. It
transfers and moves
● Joules is a pretty low measurement, so kJ (1000J) or mJ(1000000)
will often be used
1.2
● W hen a magnet magnetizes and demagnetizes in the coil, energy
loss happens: some of the energy is unnecessary heat energy.
Enlarging the voltage minimizes energy loss
● What really happens in a transformer?
There’s a magnet surrounded by soft iron, and in a coil. Soft iron
demagnetizes and magnetizes the magnet very easily and quickly:
when the magnet “moves” energy is generated from the coils,
because of the change of voltage
● P = U times I
P is power in watts
I is current in amperes. Current can be explained as how much
water move in the river in a second
U isvoltageivolts.Voltagewouldbehowmuchwindisneededfor
the current
● Inside every electrical appliance there’s a transformer
● 230V standard from the wall “mains voltage”
● Hz is how many times the voltage alternates per second
1.1
● The production of energy happens in a power station
● H ow does the production of electricity happen then?
1. Coolant water enters theboiler
2. In the boiler, the water is vapourized under a veryhigh pressure
3. The water, high pressure water vapour enters the turbine, in
which the spinning motion happens (with a sort of rod)
4. The spinning water vapour enters the generator, in which with
the spinning “rod”, energy of movement is turned into electrical
energy
5. The unnecessary water vapour from the turbine goes into the
condenserwhere it is cooled down again
6. The water vapour from thegeneratorentersthetransformer,in
which a magnet is magnetized and demagnetized by soft iron on
coil. Electricity is created!
● P = E over t
P is power inwatts.WattsisJ\s.powermeanshowmuchenergyis
produced in a second
E is energy in J
t is time in seconds
● E = P times t
, t = E over P
●
● Remember: energy doesn't appear\disappear, or get created. It
transfers and moves
● Joules is a pretty low measurement, so kJ (1000J) or mJ(1000000)
will often be used
1.2
● W hen a magnet magnetizes and demagnetizes in the coil, energy
loss happens: some of the energy is unnecessary heat energy.
Enlarging the voltage minimizes energy loss
● What really happens in a transformer?
There’s a magnet surrounded by soft iron, and in a coil. Soft iron
demagnetizes and magnetizes the magnet very easily and quickly:
when the magnet “moves” energy is generated from the coils,
because of the change of voltage
● P = U times I
P is power in watts
I is current in amperes. Current can be explained as how much
water move in the river in a second
U isvoltageivolts.Voltagewouldbehowmuchwindisneededfor
the current
● Inside every electrical appliance there’s a transformer
● 230V standard from the wall “mains voltage”
● Hz is how many times the voltage alternates per second
