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Back Emf (1 Viewer)
- Thread starter Cheezy-G
- Start date
zenger69
Bok Choyer
Back emf occurs only in motors.
When coil of the motor turn, they cut field lines. Therefore when the coil cuts field lines, it creates an emf (back emf as it opposes the normal emf going through the coil) as there's no load.
Therefore to abide by the law of conservation. Without this back emf, the coil would spin to an infinite speed as it has no resistance to slow it down.
Hope it helps.
When coil of the motor turn, they cut field lines. Therefore when the coil cuts field lines, it creates an emf (back emf as it opposes the normal emf going through the coil) as there's no load.
Therefore to abide by the law of conservation. Without this back emf, the coil would spin to an infinite speed as it has no resistance to slow it down.
Hope it helps.
Budz
Member
took me a while to get my head around this idea, but considering im doing it now ill try and help
A motor = a current carryin conductor within an external magnetic field. It works because of the motor effect. this causes motion, usually in motors rotational motion...
You now have A conductor moving realative to a magnetic field.
A conductor moving within a magnetic field = A generator
A generator produces an emf. Thnks to Lenz "reletive motion between a conductor and a magnetic field produces current which opposes the original force"
And hence the emf flows in the opposite direction... 'back emf'
why, refer to zenger69 and conservation of energy
A motor = a current carryin conductor within an external magnetic field. It works because of the motor effect. this causes motion, usually in motors rotational motion...
You now have A conductor moving realative to a magnetic field.
A conductor moving within a magnetic field = A generator
A generator produces an emf. Thnks to Lenz "reletive motion between a conductor and a magnetic field produces current which opposes the original force"
And hence the emf flows in the opposite direction... 'back emf'
why, refer to zenger69 and conservation of energy