Recent content by david13579

Homework Statement Well it is not the problem itself that bothers me but the maths behind a part of it. As part of finding the coefficient I had to solve the integral of (Sin(x))^(2l+ 1). The solution given by the solution manual just pretty much jumps to the final answer...

And now, after further thinking I even see that the constraint is what prevents g from being the acceleration in the y direction. mg-λ=mgsin2(a) which would be the force in the y direction with the acceleration I found. :) Thanks a lot.

Here are 2 of my attempts at it: without constraints http://i.imgur.com/wQ9RKSA.png With constraints http://i.imgur.com/7zvNv6w.png both give me the same result. And like I said before, if I draw on paper and try it as a problem of breaking vectors into components, I get the same answer but then...

Doing the same question with constraints is a separate question so there has to be a way without constraints. The first question is to do it and the second is to do it again using a constraint (which I think should be f(x,y) = y-xtan(theta)=0 And no, I don't know rotation matrices.

Homework Statement I'm asked to solve the typical intro level box on an inclined plane problem but I need to do it using the lagrangian. My difficulty with it is that the axis I am required to use are not the typical axes used when solving this using Newtonian mechanics. Instead of the...

2.62 for large to small 0.382 for small to large

OMG, that's it, that's it. Thanks. This is something very simple and obvious, I don't know how I could have missed it. It is also easy enough that I can picture a professor asking for it. Now I feel embarrassed by not realizing myself. Interesting enough, the ratio found using the method I...

Hmmm dividing all by C22... that is a bit that never occurred to me, making the actual ratio the variable. I'd end up with 2 solutions, reciprocal to one another. So I guess that is what Wolfram did then, since it does give the answer in terms of the 2 variables and I just solved for the ratio...

Oh I found the answer on my own. I had already come to the equation (C1+C2)2 / C1C2=5 but it was impossible for me to solve. Wolfram Alpha now gave me an approximate answer and it is the ratio indeed.Is there another way of going about this? I doubt a professor would want students to solve such...

Homework Statement Two capacitors connected in series store energy U. Now the two capacitors are connected in parallel to the same voltage source and have energy 5U. What is the ratio of the larger to small capacitor?Homework Equations For series capacitors Ceq=C1C2/(C1+C2) For parallel...

Let me try I think you were doing fine but substituted the wrong charge: Q=ρV=ρ((4/3)πa3) therefor ρ=Q/((4/3)πa3) for the new volume inside the sphere then q=ρ/((4/3)πr3) if you substitute those to what you found then you get E = q in / (4πr2ε0) = ρ((4/3)πr3)/(4πr2ε0) this equals ρr/3ε0 and...

N/C is equivalent to V/m. There is no need to worry about conversions. The units of K cancel with the ones for q and r^2 to give you N/C

Homework Statement This is the problem: http://i.imgur.com/MrRwi.png I'm not exactly looking for a solution to the problem, I am looking for a solution to the conflict created by different methods I've seen of doing it. Cramster's method gives an answer of 87.5 and a solution manual i have...

Thanks a lot man. So in the end it comes to e=b=d>a>c

Rank the buoyant forces exerted on the following five objects of equal volume from the largest to the smallest. Assume the objects have been dropped into a swimming pool and allowed to come to mechanical equilibrium. If any buoyant forces are equal, state that in your ranking. (Use only ">" or...