Re: CIM quiz
 

Being a mechanical subteam is no excuse to not know this; personally, anyone on my team that is working design MUST know at least half of this stuff to do any work.

Re: CIM quiz
 

Being on mechanical means that you should know this. You can never design anything well if you don't understand the big picture.

Re: CIM quiz
 

True, but in the context of the FRC, knowing exactly how back-emf and inductance losses play into a motors performance isn't critical to design, although I do agree that knowing the effects that voltage, torque and load play into the operation of the motor are necessary.

Re: CIM quiz
 

Please note that back emf does not cause any "losses". It simply limits the amount of current that the source can deliver to the load.

The losses in the motor are due to I^2R heat in the motor windings, motor bearing and brush friction, windage, and core losses (hysteresis and eddy currents).

Re: CIM quiz
 

Poor word choice on my part; I was referring to two separate concepts, inductance-related losses AND back-emf.

Re: CIM quiz
 

Aha.

In that case, I would argue that understanding back emf is pretty important for understanding why a DC motor does what it does.

For example, back emf is the reason for the relationship between applied voltage and motor speed at constant load torque. If Ke is constant, then for constant load torque the speed varies linearly with applied voltage.