Recent content by Luke Cohen

Awesome. you are a huge help. Thanks so much!

Okay, so I get u^2 - 2Eu/k + L^2/mk = 0 using the substitution u = r^2. After that, I use the quadratic formula, then square my answer to get r. That would give me my Rmin and Rmax? Is the physics I performed correct in the above equation? Thanks for the help thus far.

substituting what though? the only common term is 1/k, but that wouldn't help

I had been working on that for a while and couldn't figure anything out. Can you point me in the right direciton?

ah, okay so my quartic equation was correct. I said E = L^2/(2mr^2) + kr^2/2 giving me a quartic equation of r^4 - 2Er^2/k + L^2/(mk) = 0

I don't think I did, as I was going under the assumption that dr/dt = 0, which I can see now only applies for circular motion. Is there a particular direction you think I should tackle this problem from? It says I need to answer in terms of E and L, and I am really stuck on how that is possible.

For the first part, it's an r hat. And dang, you're right about the second part. I am going to change that. How should I go from there?

Homework Statement A force field in 2-d F~ = −kr(rˆ) with U(r) = k(r^2)/2 acts on a particle of mass m. The particle is now in a non-circular orbit. In terms of the particle’s angular momentum L and energy E, d) What is its closest approach to the origin? e) What is its furthest distance from...

I don't think my professor would assign anything requiring a computer algebra system... I am also sure that I should be able to solve this problem with the LT equation above for Ux and then the LT equation for Uy. Is there something I am doing incorrectly with my assigning of values to the...

Homework Statement Two rockets leave their space station along perpendicular paths, as measured by a flight controller on the space station (see figure). The flight controller records the speeds of Rockets 1 and 2 to be 0.6 c and 0.8 c respectively. What is the velocity of Rocket 2 as measured...

This is just a normal box series RLC circuit with a battery, resistor, capacitor, and inductor in series. Sorry for not including!

Homework Statement The current in a series RLC circuit leads the generator voltage by φ = 30°. The circuit, containing an inductor L = 400 mH and a resistor R = 50 Ω, is driven by a generator operating at ω = 100 rad/s with a maximum emf of 10 V. The capacitance is unknown. The first question...

Homework Statement If the angular frequency of the generator exceeds 1/sqrt(LC), the average energy stored in the inductor is greater than the average energy stored in the capacitor. True of False? Can someone explain to me the derivation of this answer? Homework EquationsThe Attempt at a...

What if you had a magnet and drew a circle from the north to the south pole. This circle had the same radius from the center of the magnet.

http://www.physics.sjsu.edu/becker/physics51/images/28_03_Earth_magnetic_field.jpg If this is your magnetic dipole and you start at the north end and follow a field line to the south end, is the magnetic field equal in magnitude the entire way through?