Recent content by Robsta

I also have a question about the second part of the question visible in the image above. The question is "Use symmetry to explain why the neutral rho meson does not decay to two neutral pion". My argument goes like this: The parity of neutral rho is (-1) (since L=0). The parity of a neutral...

Attached is a picture of the relevant curves in case it adds anything. Although I've labelled the width Gamma I am aware that it's a graph of energy of decay against frequency of decay.

Homework Statement I've got a given Breit Wigner curve of the number of decays at given energies. I've been told by several sources that the width (FWHM) of the curve gives the rate of the reaction. I can't see however how an energy here actually translates into a rate. Homework Equations I...

Hello all, I'm going to investigate the properties water when frozen in a strong electric field for a product I'm designing. A strong field will align the polar water molecules, and then they will freeze. I'm planning to create this strong field with a car battery attached to two parallel...

Homework Statement Why is it harder to rip off a paired electron than an unpaired electron? I'm trying to work out why the ionisation energy is lower for chlorine than for argon. Homework Equations Configuration for argon: $$1s^22s^22p^63s^23p^6 $$ Configuration for chlorine...

Homework Statement A person (mass 57.8 kg) tries to penetrate a garden fork (mass 1 kg) into a melting block of ice by standing on it with all his/her weight. Assume that no heat flows from the fork to the ice. The fork has four prongs, and each prong has a square cross section of area 1 mm2 ...

Gah! I've just realized that the wire moves PERPENDICULARLY to the wire. I thought it was moving parallel. This means the magnetic field does change and thankfully a current is induced. All solved

Homework Statement [/B] 3. A square loop of area a 2 is formed from a single turn of thin wire of resistance R. The loop is aligned with two sides parallel to an infinite straight thin cable, with its closest side a distance r away, and is given a velocity v in a direction perpendicular to the...

Homework Statement A quantum-mechanical harmonic oscillator with frequency ω has Hamiltonian eigenstates |n with eigenvalues En = (n + 1/2) ħω. Initially, the oscillator is in the state (|0> + |1>)/√2. Write down how the state of the oscillator evolves as a function of time t. Calculate the...

Homework Statement I've uploaded a diagram showing a two beam interferometer that can be used to monitor changes of refractive index in a gas cell. it is illuminated with monochromatic light of wavelength λ. The light is linearly horizontally polarised. The two polarizing beam splitters (PBS)...

Okay I've drawn a diagram and had another thought. if Ex and Ey describe points on an ellipse with equal radius, they must be at ±π/4 relative to the major and minor axis. So θ = ±π/4 Here's the diagram I did to convince myself that this must be the case. Trying to work out what to do next now.

Looking at this more, does φ have to be 90 degrees always? Two waves have the same phase difference no matter what frame you view them from, right?

Homework Statement Consider an elliptically polarized beam of light propagating along the z axis for which the E field components at a fixed position z are: Ex = E0cos(ωt) and Ey = E0cos(ωt +φ) Find the major and minor axes of the ellipse in terms of E0 and φ and sketch the ellipse in the...

Oh yes, that's exactly right, thanks very much. Was staring at this for ages, much appreciated :)

Homework Statement Work out the variance of momentum in the infinite square well that sits between x=0 and x=aHomework Equations Var(p) = <p2> - <p>2 $$ p = -i\hbar \frac{{\partial}}{\partial x} $$ The Attempt at a Solution I've calculated (and understand physically) why <p> = 0 Now I'm...