# Search results

1. ### How does a Dynamitron accelerator work?

I'm having trouble understanding how a Dynamitron accelerator works. I found this image online Would anyone be able to explain how this system accelerates the electrons? Thank you
2. ### Radius of the path of an electron in a magnetic field?

Thank you for the reply. I corrected the formula for r, and I took your advice and related energy to momentum. results: r = \frac{p}{qB} = \frac{\gamma mv}{qB} E^{2} = \left(pc\right)^{2} + \left(m_{0}c^{2}\right)^{2} p = \frac{\sqrt{E^{2} - \left(m_{0}c^{2}\right)^{2}}}{c} p =...
3. ### Radius of the path of an electron in a magnetic field?

Homework Statement 15MeV electrons, enter magnetic field with strength of 0.7T. What is the radius of the path of the electrons? What energies could the electrons have and be confined to orbits with radii within 5% of the 15MeV electrons? Homework Equations E =...
4. ### Energy loss of an electron through Air?

Homework Statement What is the energy loss in 3 mm of air (density = 1.20479E-03) of an electron with energy of 1.77MeV? The Attempt at a Solution I've found the Mass stopping power which is 1.696 MeV cm^2/g and then linear stopping power of 2.04E^-3 MeV/cm but from this point I'm stumped...
5. ### Find half-life from an atomic ratio?

Homework Statement An equilibrium ore mixture has an atomic ratio for \frac{U-235}{Pa-231} = 3.04x10^{6} Find the half-life of U-235 from the data. The known half-life for Pa-231 is 3.28x10^{4} years Homework Equations For secular equilibrium \frac{\lambda_{2} N_{2}}{\lambda_{1}...
6. ### How to show group velocity = particle velocity?

Would this work also? V_{g} = \frac{d\omega}{dk} = \frac{dE}{dp} = \frac{d}{dp} \frac{p^{2}}{2m} =\frac{1}{2m} \frac{d}{dp} p^{2} =\frac{1}{2m} 2p =\frac{p}{m} =\frac{mv}{m} =v
7. ### How to show group velocity = particle velocity?

Sorry, what's \gamma? I've always learned that Momentum = Mass*Velocity?
8. ### How to show group velocity = particle velocity?

Thanks for the hint, however I'm still really stumped on what to do next. I divided and squared both sides and I get this: V_{g}^{2}(p^{2}c^{2}+m^{2}c^{4})=pc^{2} I've tried subbing in p=mv and I get: V_{g}^{2}(m^{2}v^{2}c^{2}+m^{2}c^{4})=mvc^{2} Pull out an m and...
9. ### How to show group velocity = particle velocity?

Homework Statement In an electron wave, show that the group velocity = particle velocity of the electron Homework Equations E = p^{2}c^{2} + m^{2}c^{4} The Attempt at a Solution V_{g} = \frac{d\omega}{dk} = \frac{dE}{dp} = \frac{d}{dp} \sqrt{(p^{2}c^{2} + m^{2}c^{4})} =\frac{1}{2}...