Okay, this may be a bad question but for the graph in A ii) my intuition is telling me that at T1, the graph needs to sharply decrease to 0, as the object is at rest and, therefore, there cannot be an acceleration. Why is that not part of the answer? Thanks for the fantastic videos man!
3 years later, and this is a good question, and im assuming there would be nothing wrong in doing this as the friction torque should stop once it stops moving. I would like to know the answer though.
Yes. There is nothing in the problem description which tells you the rate at which the angular acceleration changes. All you know is that the angular acceleration gets closer to zero. As long as you show that, you still get the point. (This graph was only worth 1 point.)
For part (D), to get full points would we need to show the entire derivations and equations or can we just say the words/reasoning (like, equation 1 is not plausible because it implies the torque is increasing linearly with time when in reality increased oil should cause less friction and thus less torque, which is what equation 2 shows since t is in the denominator and so it is inversely proportional).
Generally my solutions are a bit more detailed than they need to be. I am doing my best to absolutely make sure you understand my answer. I would think your all word answer would be sufficient for full points.
Time 1 is the time at which the when reached an angular velocity of zero in part (a) when there was a greater average torque on the wheel than in part (c). Therefore, with a smaller average torque in part (c), it will take more time to reach an angular velocity of zero.
For part c, why would it be wrong to say that the slope is not curved for angular velocity? I'm a bit confused as to why it's curved.
Thanks for making these they've been really helpful in quarantine
Okay, this may be a bad question but for the graph in A ii) my intuition is telling me that at T1, the graph needs to sharply decrease to 0, as the object is at rest and, therefore, there cannot be an acceleration. Why is that not part of the answer? Thanks for the fantastic videos man!
the acceleration is negative, and its at a constant because the velocity is constantly decreasing to zero.
3 years later, and this is a good question, and im assuming there would be nothing wrong in doing this as the friction torque should stop once it stops moving. I would like to know the answer though.
Could you still get points if you graphed the angular acceleration graph in part c after 1/2t quadratically instead of linearly approaching alpha=0?
Yes.
There is nothing in the problem description which tells you the rate at which the angular acceleration changes. All you know is that the angular acceleration gets closer to zero. As long as you show that, you still get the point. (This graph was only worth 1 point.)
At 7:53 wouldn’t it be 11 points total
For part (D), to get full points would we need to show the entire derivations and equations or can we just say the words/reasoning (like, equation 1 is not plausible because it implies the torque is increasing linearly with time when in reality increased oil should cause less friction and thus less torque, which is what equation 2 shows since t is in the denominator and so it is inversely proportional).
Generally my solutions are a bit more detailed than they need to be. I am doing my best to absolutely make sure you understand my answer. I would think your all word answer would be sufficient for full points.
Im confused why in part b t0 is negative
in part c, why dosent angular velocity reach zero? I though it comes to rest
Time 1 is the time at which the when reached an angular velocity of zero in part (a) when there was a greater average torque on the wheel than in part (c). Therefore, with a smaller average torque in part (c), it will take more time to reach an angular velocity of zero.
@@FlippingPhysics got it thank you so much!
Reflection Of Light Please
These would be helpful but nothing is explained