Recent content by Dragster

Oh well I am really stupid after all. Thank you cepheid et harusphex :) First university session makes me feel like a complete ignorant idiot.

I added the black circle with the ''?" on the top right. Do you mind if I can get the rigorous explanation why the arc is Rθ? Thank you for the fast answers Oh yea and for the problem, the string is attached on a cylinder. At theta = 0 with the vertical, the length is l0 and the asked result...

How do they get from the Rsinθ the value I have found the one I search: Rθ (extra string length) I know that sinθ = θ when θ is small but there Rsinθ is the extra height the mass gain when we push it from initial position to a θ angle with vertical, I don't see how it could be the extra...

Okay right the mass of the object being the liquid accelerated increases as the volume increases but what does the integration of dm gives? If I start from the beginning with 2nd law, F = ma = cv^2 m = cv^2/a dm/dt = cv^2/a dm = (cv^2/a)*dtI know that the mass of the liquid is equal to p*V so...

http://img12.imageshack.us/img12/1158/physich.png My question is probably stupid but what is dm? V is π*r^2*v since v=dx/dt the volume increases over time. So dV/dt = π*r^2*dx/dt The object encounter the medium at the rate of ∂Av because Av is the volume of fluid and ∂ is the density...

http://img27.imageshack.us/img27/1158/physich.png I really do not see how I can solve the problems. All I need is hint how to start the problems most of the time. I know I should read more, ask questions to teacher, etc. I have 5 classes, 5 homeworks to do every week. On top of that I have...