6.4 Generating Electricity Flashcards
according to N3L if a magnetic field occurs then
then an equal and opposite electric force occurs
how can we conduct an electrical circuit through the wire using a magnetic field
if we apply a magnetic field to the wire an e.m.f will be produced and the electrons in the wire will start to move in the opposite direction causing electricity to be generated
if we change the direction of the magnetic field (polarity) that is applying an e.m.f on a wire what will happen
the polarity of the E.M.F will reverse reversing the current direction
what does faraday’s law state
the induced e.m.f (by the magnetic fleid) is proportional to the rate of change of flux linkage
how can we investigate Faraday’s law
by using a magnet, a coil of wire and a voltage datalogger
what is Len’s law
the direction of induced E.M.F is such as to oppose the change creating it
what is a primary coil
it is the first coil in a transformer, through which a supply current passes
what is a secondary coil
the second coil in a transformer, through which the output current passes
how does a transformer work
when the primary coil switch is closed a magnetic field caused by the Np, meaning the changing of magnetic field will be acting on Ns, so due to the change in flux linkage an induced E.M.F will be produced
when the electromagnetic field is stable in the transformer what will happen
the change in flux linkage will be zero, which means no more induced e.m.f
when the primary coil switch is opened what will happen
The magnetic field will disappear causing an E.M.F in the opposite direction, causing the needle in the voltmeter to kick the opposite way and return to zero
what will happen to the voltmeter when we open the switch of the primary coil in a transformer
the needle will kick in the opposite direction and then return to zero
why do we use soft iron for the core in transformers
because it is easily magnetizable
using an altering current in a primary coil causes
the electromagnetic field produced by the primary coil is varied, causing the induced e.m.f at the secondary coil to be varied
the e.m.f of the secondary coil varies at the same rate as
as the I (current) supplied to the Pc and depends on the rate of flux linkage
