haruspex's latest activity
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haruspex replied to the thread Proof of law of sines using cross product.I see no reason to doubt @BelieverOf143___ understands that. If the vector product rule can be used to prove the law of sines then... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.I do not see how it was clear that the last equation in post #52 was wrong without doing the simplification. Maybe you are better at... -
haruspex replied to the thread Proof of law of sines using cross product.When given a task like this, you have to start with the definitions you are expected to work from. State the law of sines and the... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Obviously you had done those steps, so I expect you to post where you actually got to, not several equations back, making me redundantly... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Well, obviously, the usual steps of cancelling out the non-infinitesimal terms and discarding the second order infinitesimals. What... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.I alluded to that in post #44, but I think it is ok because we can instead view it in terms a tension transmitted around the curve and... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.But that element is the "exhaust". The loss of it is removing momentum from the system. It is the water leaking from the cart. -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Right, but it does affect this: -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Yes. Right, but that's rocket+fuel+exhaust, which is a closed system. There are two issues here. First, somehow an element leaves the... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Ok, I understand now. You have fallen into the classic trap of applying ##F=\frac{d(mv)}{dt}=v\frac{dm}{dt}+m\frac{dv}{dt}## to a... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Are you writing multiple lines of LaTeX inside one pair of $ $ brackets? Try not doing that. And please use the preview button... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Please show the details of your differentiation of the horizontal momentum. Looks like you missed a term. -
haruspex reacted to jbriggs444's post in the thread Chain falling out of a horizontal tube onto a table with
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It could if, for instance, we let the chain ride in a frictionless tube on the table. Then the section of chain in the tube would be... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Since the problem statement does not specify what happens to the chain on reaching the table we have to make a reasonable guess about... -
haruspex replied to the thread Chain falling out of a horizontal tube onto a table.Whether it’s a track over a smooth shoulder or a massless pulley is clearly independent of whether the problem concerns a massless...