Recent content by sinas

I don't even know where to begin here, could use a hint =/ "Two positive ions having same charge q but different masses, m1 and m2, are accelerated horizontally from rest through a potential difference V. They then enter a region where there is a uniform magnetic field B normal to the plan...

kk thanks :smile:

Is there a way to show that the error in stirling's approximation goes to zero as n goes to infinity?

Ahh that works out nicely... n!=~n^n*e^-n*(2*n*pi)^(1/2) which leaves me with... sum from n=1 to infinity of (2*n*pi)^(1/2) and sum from n=1 to infinity of (-1)^n*(2*n*pi)^(1/2) and in both cases the "infiniteth" term doesn't go to zero, so both diverge... is my reasoning sound?

Don't know what that is but I'll look it up in a sec...

The original series is the sum from n=1 to infinity of (n!*x^n)/(n^n) I used a ratio test to find that the interval of convergence is -e < x < e But now I need to test the endpoints, which means I need to find if the following two series converge: sum from n=1 to infinity of...

BTW thanks both of you for the help :smile:

So if your car has the same momentum going into each collision, and has 0 final momentum (mass*0 velocity?), then delta p for your car (and thus the force) is the same for each?

average force = impulse/time If the times are the same, then it just depends on the impulse, which is change in momentum... For the two cars.. m(50)+m(-50)=2m(0) delta p = m(50) ? For the wall..

Consider two situations: 1) You are driving 50 mph and crash head on into an identical car also going 50 mph. 2) You are driving 50 mph and crash head on into a stationary brick wall. In neither case does your car bounce off the thing it hits, and the collision time is the same in...

x=--x wtf =/ (this isn't a homework problem but it was brought up today and I'm curious) :confused:

Ok I'm playing with that, but tell me something - if I were to calculate the work moving the entire string from 0 to the y-coordinate of the centroid of the curve, that wouldn't work, right? (no pun intended)

Hi - Here's the entire problem to avoid confusion >< "A kite is flying at a height of 500 ft and at a horizontal distance of 100 ft from the stringholder on the ground. The kite string weighs 1/16 oz/ft and is hanging in the shape of the parabola y=(x^2)/20 that joins the stringholder at...

Got it, thanks =)

limit as x->infinity of [(x^2-6x+1)^(1/2)-x] I have tried to force it into a l'hopital form without much success, and tried to look up a couple different techniques (like replacing x with 1/u and finding the limit as u->zero) but I honestly don't even know where to begin.