Answer / divya kumar sharma

in electrical machines it is the air gap which helps in
transfer of the energy from stator to rotor or from rotor
to stator. it also tells about the energy handling capacity
of the machine.

Answer / er. ankush miglani 9718151073

air gap is harmful not usefull

Answer / antony

AIR GAP IS THE PART OF THE MACHINE WHICH STORES THE MAXIMUM
AMOUNT OF STORED ENERGY(REACTIVE POWER WHICH PRODUCES
MAGNETIC FIELD AND GIVEN BACK TO SUPPLY)... IT ALSO REDUCE
THE FRICTION LOSS........ GIVES RELUCTANCE

Answer / sunil guru

Air gap is only useful when the gap is in standard value...
if the air gap increases (is more than the m/c
specification)..
then it creates the losses like iron loss,stray load
loss,friction and windage losses...
also the reluctance and blunging (commonly known as fringing
of flux) increases.... and results in reducing the efficency
of machine...
good air gap helps to create the flux,circulating current and
finally the torque.....(here the flux is totally used)..
(less losses)

Answer / anupam

though it reduces friction still it is not very desirable
because it increases loss,also it produces harmonics which
is responsible for early starting of motor(about at 1/7 of
rated speed)ie crawling.

why doesnt the back emf hold the speed of unloaded series motor?

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