That is indeed a well thought out and explained lesson/video. However, you misinterpret his statement. @ 8:08 in that video, he is talking about the generator, not the motor. He refers to the increased resistance to turning of "IT". "IT" being the generator that "he", the student, was cranking.
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Switching my discussion over to the generator "trying to turn in the opposite direction" ...
I can understand saying that a resistance to movement is an "attempt" to move in the opposite direction. That is certainly an easily understood concept. This is also especially understandable since if you instead, force a current through the generator in the same direction that it flows when it is generating, the generator's motor behavior will indeed turn it in the opposite direction (I might add, a good demonstration of Fleming's Right & Left Hand Rules). However, I would not say it that way because we are not forcing a current through it from an external source and, therefore it is operating in the mode of generating current from a force/movement/ not in the mode of producing movement from a current. I like the way he uses the mechanical movement as the electric-magnetic link and my proposed explanation fits very well with the two step introduction to the motor/generator concepts in the video.
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I believe a better overall view is, at that time, to focus on the concept that a resistance to movement isn't necessarily trying to *MOVE* opposite than the initial movement. Certainly, you must agree that the resistance (friction) you feel pushing a brick along the ground is simply resistance (friction) to movement and not an attenpt to actually move backwards.
As he does later in that same video, I think it is more instructive to consider the resistance to the movement felt at the generator's crank to be an additional energy (input) that is required to now be delivered to another device such as the headlamp.. This also easily focuses on the very thing he later criticizes about the "Free Energy" supporters.
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So... Yes it can be said that, in a way, a loaded GENERATOR 'appears to" try to turn in reverse when loaded... but an understanding of the flow of energy from mechanical, to electrical, to some other useful form is a good thing to introduce at that point.
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Cheers, ScienceAdvisorSteve
P.S. Made me think carefully about this...and, yes, after doing the Fleming left hand and right hand manipulations in the air, I also had to take a DC motor and verify to be sure my interpreting things correctly, that the directions of the currents and rotations for this discussion...
Science works and always applies.
When I worked for a used electronics place, I used to display motors removed from large computer tape drives like this to demonstrate how efficient they were to sell them....before that they just sat on the shelves, after I connected 2 on display with a sign saying "turn me" they all sold out....;-)
Great way to show how a motor and alternator are basically the same thing. A motor can be an alternator and a motor, the same applies to a alternator. When a load is applied to a motor it basically tries to move in reverse which is why it takes allot more power to run a motor that is under a load.
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