Thanks for the prompt reply, but I don't quite follow. Could you clarify what you mean by 'not needing a wave function'? I feel I am approaching the problem from the wrong angle.
Homework Statement
A one-dimension system is in a state described by the normalisable wave function Ψ(x,t) i.e. Ψ → 0 for x → ±∞.
(a) Show that the expectation value of the position ⟨x⟩ is a real quantity. [1]
(b) Show that the expectation value of the momentum in the x-direction ⟨p⟩...
I was doing a question while back about finding the de Broglie wavelength of a bullet with a given mass traveling at a given speed- easy stuff. However, when the result was very similar but slightly larger than the Planck length which I'd stumbled across on my few jaunts through Wikipedia, it...
Basically, I had a mahoosive 'DUUUUUUH' moment so it's all sorted. It only comes down to half a page of working now.
First, have a look at this.
http://en.wikipedia.org/wiki/Kinetic_theory
We know pressure, volume and how many times an atom of He hits the wall of the container per second...
Homework Statement
A quantity of helium gas is held in a square box 1 m length. The measured macroscopic pressure of the gas is 1000 Pa. An atom of helium makes 500 collisions per second with the wall of the container traveling at an average velocity perpendicular to a wall of a container...