Recent content by haruspex

Agreed - I only said "according to the calculation". The pump can only generate a flow by raising pressure. However, once a circulation is established the generated pressure only need be enough to overcome drag.

Yes: https://en.wikipedia.org/wiki/Electrostatic_induction#Induction_in_dielectric_objects

Also known as induction.

My guess is that there is some head of water providing pressure and the pump merely circulates the water at the bottom in some horizontal loop, the rate through the wider portion being set to ##v_1##. According to the calculation, with the pump on, air will be drawn into the loop and bubble up...

The trick is to handle the vertices in the right order. Which vertices will be the most problematic? Deal with those first.

As in post #7? Am I missing something?

So apply ##\vec F=m\vec a## and consider what can produce that ##\vec F##. No, I meant with the apex of the cone at the centre of the turntable, so that the only difference from the given problem is that the cone is not rotating on its own axis. I am puzzled that you keep referring to a...

Do you have to do something about the contact points? I don’t understand the question. Yes. Can you answer my questions in post #3?

I assume the rotation rate is constant. What is the acceleration of the cone's mass centre? What do you deduce from that? Would it be different if the cone were mounted on a rotating turntable instead of rolling? If it is on a fixed surface and not slipping, what can you say about the...

I am sorry, but I am rather snowed now. I'll try to get back to this in a day or two.

A smoother result can be had by interpolating with splines, e.g. cubic splines: https://en.wikipedia.org/wiki/Spline_interpolation

It isn't clear to me whether reflections are considered to be the same, e.g. is YRRBB the same as YBBRR? If so, there are only four.

Thinking about it some more, I have decided it is not helpful to describe it the way I did, with the ##\lambda v^2## being subtracted from the tension both sides. That would make sense if the quadrant contained a contraption that first brought each element of the horizontal stream to rest then...

Now I'm confused… you previously mentioned "indagate", an archaic but valid word meaning to investigate, from the Latin "indagare". "Indigate", as used in your post #27 seems like a misspelling of "indicate". Though it could be useful to describe e.g. wagging one's finger at a queue jumper...

The retardation force on the horizontal portion is not the only reason the tension reduces. Consider a massless string but with a mass on each end. The tension is reduced when accelerating even though there is no retardation force. This corresponds to the ##-\lambda\frac{dv}{dt}## term in the...