change in current in DC motor (1 Viewer)

[thaoroxy2001]

how did you guys explain the change in current in the DC motor when its axle was held?

 

[BillyMak]

Back emf is not produced when the motor is prevented from turning, so total voltage is greater. Resistance is constant, so current is directly proportional to voltage. Since voltage is greater, current is greater.

That, but over about 15 lines.

 

[thaoroxy2001]

crap....I'm screwed then cause I didn't even mention back EMF. I just talked about the orientation of the coil relative to the magnetic field or sumthing like that...now....I'm really screwed.

 

[kunny funt]

i always dont see the simple shit, i went on about how the law of conservation of energy applies and electric motors are used to convert electrical energy into kinetic energy and by stopping the rotation of the motor, the release of kinetic energy is effectively stopped increasing the electrical energy and thus higher voltage and therefore current will flow in the coil.

 

[hfis]

i always dont see the simple shit, i went on about how the law of conservation of energy applies and electric motors are used to convert electrical energy into kinetic energy and by stopping the rotation of the motor, the release of kinetic energy is effectively stopped increasing the electrical energy and thus higher voltage and therefore current will flow in the coil.

Yep, me too.

 

[Gesus]

i always dont see the simple shit, i went on about how the law of conservation of energy applies and electric motors are used to convert electrical energy into kinetic energy and by stopping the rotation of the motor, the release of kinetic energy is effectively stopped increasing the electrical energy and thus higher voltage and therefore current will flow in the coil.

That answer would have been fine, full marks if you just wrote the letters 'back emf'

 

[Prerna]

Me Too

i related it to the equation Ploss=current squared * Resisitence
therefore if you hold the axel.... as you said heat is dissapated and therfore power loss increases and thus so does current. My physics tutor said that it may be okay....i absolutly hate motors and generators loved the superconductors though


Cheers