Recent content by kuruman

An easy way to view (and teach) such problems is to consider the missing material. Here is what I mean. Start with two identical metal disks. Disk A is the control and disk B the object of investigation. Allow disks A and B to reach equilibrium at common temperature T1. Cut out of disk B two...

Sure, but how does the symmetry relate to the solution? How will you explain this to a student who is trying to understand how to solve the problem using intervals rather than equations? How does ##t_0## figure in all this?

You might, but then you need to justify it. The second half of your equation, $$\frac{\sqrt{2gH}}{\sqrt{\frac{2H}{g}}}=g$$is an identity and doesn't contribute anything new. You need to justify the first half, $$\frac{\sqrt{2gH}-\sqrt{2g(H-h)}}{\frac{1}{2}t_0}=g.$$ The numerator is the speed...

That would be the control or placebo thermocouple. A second thermocouple wrapped in wet toilet paper and placed in front of the fan would clinch the argument.

I don't think so. OP asks about cooling a person, not a thermocouple. :oldsmile:

I think that wind chill is the main cooling mechanism as confirmed by @greypilgrim is the main process here. Water loss through evaporation from the skin is a continuous, natural, and unavoidable process hastened by the fan. An estimated average of one pint of water daily is lost by humans...

Therein lies the rub. If you intend the students to use the interval kinematic analysis as a tool for answering conceptual type questions, i.e. no numerical calculations, then it's fine. If you want your students to calculate numbers, they will have to memorize one or more equations to use as a...

Here are my comments, since you asked. This approach is, of course, limited to cases where the acceleration is constant. Under constant acceleration, one has to solve the differential equation ##\ddot x = \text{const.}## and get two equations incorporating the initial conditions, $$\dot...

From a utilitarian point of view, how useful is your approach to formulate a mathematical description of physical events occurring around us? Take the simple case of two point masses ##m_1## and ##m_2## travelling in opposite directions and colliding elastically. You could use Dirac delta...

I don't know what that means. For example, an ice cube is a collection of water molecules in "condensed form." If I add enough heat to un-sustain the condensed form by converting the ice cube into steam, do the free H2O molecules constitute a wave? I am sure you will say no, so let's take...

So I googled "What is a wave?" and this is what I got. If you go by this more complete AI overview and not by what Wikipedia says, your question is answered.

And last but not least the pièce de résistance, a three double entendre lame joke with complete explanation. I take full responsibility for it. Why did the expectation values ##\langle \psi | H | \psi \rangle## and ##\langle \varphi | H | \varphi \rangle## change to ##H | \psi \rangle## and ##H...

What oscillation process?

This problem is on many websites and you can find an answer and explanation without looking too hard or having to subscribe or pay money to someone. I don't know if you have seen the solution and are asking for further clarifications or you are looking a starting point. In case it is the latter...

Why were ##x## and ##p_x## cited by the quantum traffic cop? [/Spoiler]