Recent content by dawn_pingpong

Homework Statement Hello, I was just thinking about this when going down the escalator today... When one goes down the escalator, one loses potential energy, and work is done by the escalator to bring you down. In a sense, energy is lost from the escalator too (as it does work). Taking that...

there's also edx.org now, MIT/Harvard version of coursera. if really need to stream on a tv, I think you can always download everything to a dvd disc, then just play on a television. there are downloaders like ytd(which I quite like) where you can download whole playlists from YouTube at the...

Thank yu very much! Now I get it:D

Oh, okay, thanks! Uh the 2nd formula is in quite a lot of places actually, though I might have misunderstood it... Places like http://www.cartage.org.lb/en/themes/sciences/physics/electromagnetism/Magnetostatics/MagneticField/Forcesoncurrents/parallelwires/parallelwires.htm and the...

Homework Statement Sorry. I know this question is on the forum somewhere, but I still don't get it... Thus. For parallel wires, at the mid-point of the wires, what is the strength of the magnetic field? Do I use the formula B=\frac{μi_{1}i_{2}L}{2∏r}, or is it the sum of B=\frac{μi}{2∏r}...

some equations for you: upward F=qE downward F=Bqv (travelling straight so upward F=downward F) Then, regarding voltage: V=E/q=(0.5mv^2)/q can you find the voltage from these equations?

oh right! thanks!

0? so the integral is just 0- \int\left[\frac{(1/t)^2}{t^2(1+(1/t)^3}\right]^1?(sorry don't really know how I'm supposed to write this...) and at 0 the integral is 0. but it seems there is something wrong with the sign, because it is negative...

Homework Statement By using substitution u=\frac{1}{t}, or otherwise, show that \int^∞_1 \frac{t^5}{(1+t^3)^3}dt=\int^1_0 \frac{u^2}{(1+u^3)^3}du Homework Equations The Attempt at a Solution Well, the reverse can also be done (making t to u). However, I don't know how to...

Homework Statement When does a Taylor's Series not converge to its original function? the commonly given example is e^\frac{-1}{x^2} But I really don't get how it works... For example if we find the series around the point x=1, then...

Okay, thank you! so basically, it is the estimation around the point x=a, and the further it deviates from a the more inaccurate? For example, evaluating the value of e, without using a calculator, we still set a=0, because thenf^n(a) will be 1, and it will be easy to calculate, though there...

Homework Statement Taylor's theorem states: f(x)=\displaystyle\sum_{k=0}^{infinity}{\frac{(f(^k(a)(x−a)^k)}{n!}} When approximating a function, we always set a=0, and it gives an approximation for the whole function. Why set the a=0? What does the a reperesent? Thank you. Homework...

Okay thanks lots! Time to redo then... :/

I'm really really sorry to hijack, but just wondering, is the answer 21.75m/s? Attempted it as practice, and just want to check the answer if I made any errors. Sorry! And Thanks!

I think it is implied by the question that the orginal pressure of both segments (ie whole system) are 1 atm, though i might be wrong.