Recent content by pcvrx560

Homework Statement Find two independent conserved quantities for a system with Lagrangian L = A\dot{q}^{2}_{1} + B\dot{q_{1}}\dot{q_{2}} + C\dot{q}^{2}_{2} - D(2q_{1}-q_{2})^{4}\dot{q_{2}} where A, B, C, and D are constants. Homework Equations None.The Attempt at a Solution I've only found...

Thanks, tiny-tim! That cleared it up for me. I didn't think about the range I was integrating over, I was just mindlessly plugging numbers into 1/t.

If I had an integral \int_{-1}^{1}e^{x}dx Then performing the substitution x=\frac{1}{t} would give me \int_{-1}^{1}-e^\frac{1}{t}t^{-2}dt Which can't be right because the number in the integral is always negative. Is this substitution not correct? Sorry if I am being very thick but I...

Wow, thanks fellas. Now I feel like I accidently tried to commit treason by asking this question, haha. But seriously, I think the biggest thing I got from this thread is a visualization of how much energy can be contained in such a small volume. I've always heard "E = mc^2" and that "c^2 is...

As far as I know, they use two coils and rely on a changing electromagnetic field to transfer electric current. So would wireless charging not work for DC current since a constant voltage would create an unchanging electromagnetic field and therefore unable to induce a current in the other coil?

d'oh, didn't think about vdv as dv approaches zero thanks!

How much fissile material, in kilograms, would, say, an Ohio-class submarine carry? If it's classified, what would be about a good estimate?

Specifically, how do you prove the quotient rule using a similar method that Leibniz used for the product rule?: http://en.wikipedia.org/wiki/Product_rule#Discovery_by_Leibniz I've tried it once for d(u/v) but I keep getting a vdv term in the denominator.