Recent content by DeltaFunction

This is just a very standard linear kinematics question that's been verbally tarted up. The point is that once the hose is moved away from vertical the last 'drop' of water to leave the nozzle hits the ground 2s later. So you're right to use 2s as the time in this case. This problem is...

All is clear now :) you have made a mistake. When in doubt, put everything in SI

I don't know I'm afraid :/

You're welcome. It happens to everyone now and then!

Ok. Can you confirm which value of heat leaving the gas is correct: 407 J or 470 J

I'm a bit vague on this too. The problem simply states "Show that the product ##<S^2_x> < S^2_y> ## is consistent with the uncertainty principle" I assumed I'd need to link that to ##ΔS_x ΔS_y## to demonstrate this, but I'm stumped by this

Something's not right here. The equation doesn't balance for the book answer of 1.42x10^8

If your answer to part a is correct, then I can't see what's wrong with your answer to part b (see EDIT) Is this a multi choice question that is automatically assessed? EDIT: Just noticed that in the question statement you say that 470J of energy leaves, but in the calculation for part b you...

Homework Statement A spin-half particle is in a known eigenstate of Sz. Show that the product <S^2_x> < S^2_y> is consistent with the Uncertainty principle Homework Equations The Attempt at a Solution I know that the generalized uncertainty principle gives ΔS_x ΔS_y ≥ |<[S_x...

Assuming I'm deciphering the equations correctly, then the first integrals equal zero because the integral will be a sin function, and between the limits you will always have integer multiples of pi for any k (sin k*pi = sin(-k*pi) = 0) The second integral is zero because it is an odd function...

when you do this calculation you actually get 1.1186 x 10^17. Many orders of magnitude faster than the speed of light. As the others have said you've just got to make sure your units are consistent.

I've realized my stupid mistake. I copied down the identity incorrectly. A moments thought and I would have seen that sinh~iθ = i~sinh~θ is nonsense :rolleyes: embarrassing

Thank you, yes it should be h^2, I've now corrected that. I guess I'll go through the figures again carefully :/

Homework Statement A steady stream of 5 eV electrons impinges on a square well of depth 10 eV. The width of the well is 7.65 * 10^-11 m. What fraction of electrons are transmitted?Homework Equations The following equation for the transmission coefficient, T, is given: T = [1 + \frac{V_0 ^2...