Recent content by pls

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    General Thoughts: Physics

    yeah thats what i did. Just totally forgot that w=mg is actually f=ma,
  2. P

    General Thoughts: Physics

    yeah good, thought you meant it was accelerating upwards
  3. P

    General Thoughts: Physics

    can't use f=ma. Its moving at a constant speed so a = 0??
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    Quanta to Quarks

    How'd everyone go? Wasn't too hard from memory but I'm pretty sure i didnt get the 2 marker about the standard model. Also with the last question, did anyone else talk about de Broglie using the pre-existing concept of 'waves acting as particles' to come up with the idea that 'particles can act...
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    Multiple Choice

    Im pretty sure that when a motor spins it becomes a 'de facto' generator, since it is effectively a conductor moving in a magnetic field and hence there will be a current created which opposes the change in flux (i.e. a current in the opposite direction of supply current) so total current...
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    General Thoughts: Physics

    +1 to the silly error count. What about the motor with the mass attached. Im not sure i got that. Did you say f=w=mg which is 0.49 N or something like that? Then for the next bit find torque using t=fd (with f from the previous question and d= radius of the shaft or whatever that was) and equate...
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    General Thoughts: Physics

    I got rotational velocity = 73.4m/s. I equated f=ma with f=mv^2/r. You get v = √ (ar). Sub in a as 9.8 and r as the radius as 550.
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    Multiple Choice

    I said torque decreases. Wouldn't back emf increase as the motor speeds up, hence decreasing current. Since t=nBIAcosø, torque would decrease?
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