# case

1. ### Special case with two falling bodies. What happens?

I came up with this problem myself and can not reach a conclusion myself so I would like to know what you think? Two hollow bodies (e.g. two cubes) begin to fall and accelerate. I look at the problem on any moment (t=T) where the windspeed U = 5 m/s. The larger cube: side 1 m and M = 3,5 kg...
2. ### Why is mass uncertain in case of Heisenberg Principle?

I read that for Higgs Boson Heisenberg Uncertainty Principle applies. But why is mass uncertain in case of short lived unstable particle? That being said the momentum is uncertain which tells us that the position is known. Is the position known by measuring the Higgs Bump? Is the velocity also...
3. ### Is classical mechanics a partial case of QM?

By that I mean can we use QM equations for calculating classical objects moving assuming their sizes >> ħ? Like we can use relativistic equations for calculation of the train speed + speed of a person in it if we want.
4. ### My Case of Total Translational Kinetic Energy of Ideal Gas

I have really problem with equation of the root – mean – square (rms) speed of the gas molecules when we use the universal gas constant (R) mentioned in all references. Accordance to all reference books, we have below equation for the total translational kinetic energy: Vrms = (3RT/ M)^0.5...
5. ### Artificial gravity - a special case?

Not really sure where this might fit best, but I'll chance it here. I was wondering if perhaps someone here might help me figure this out. I'm familiar with the concept of creating an artificial gravity in a possible future space station by spinning, for example, a cylindrical structure. But I...
6. ### Is kinematics a special case of f=mA?

Hi, Physics presents kinematics as derivative relations of position, velocity, acceleration (subject to initial conditions) of some hypothetically physical (real) object through real space. Kinematics is about unmotivated movement. Forces are not mentioned in the "real" HS kinematics problems...
7. ### case study on Inviscid Flow. Fluid jets

I have to find the thread shape r/a=(1+(2gz)/(Uo)^2)^1/4 But the only thing I have is that r/a=(Uo/Uz)^1/2 and the attached equation how rearrange the formula!??!
8. ### Weird potential energy case

Scenario: A tall chimney on 28 meters is getting demolished. Its weight is 65000 kg. The chimney falls down to the side of it, and when it has fallen 30 degrees from vertical, it breaks into two pieces and these two pieces continue to fall down to the ground. I want to calculate the speed of...
9. ### Determine the net force. State in which case the object could be at rest.

The pencil markings for Practice Question #1 is what I got but the answers are: 1. 1N[E] 2. 2N[N] 3. 0N For #1 and #2, why do I get the exact opposite in direction? Thanks!
10. ### How to Calculate temperature in this case??

(Surprised) If a metal, say tin is dragged on a surface having coefficient of friction as u, with a velocity of 60kph, then what will be the temperature generated due to friction at the surface of tin. I am in urgent need of this answer. it will be very kind of you if you send me this answer...