Recent content by neemer

Thanks for help, finally got the correct answer last night

So then i set this equal to 1/2 * 4.8 ^ t^2 and solved so I have x(t). so now I have my position vector in terms of time. r(t)=<x(t) , 0.2*x(t)^(3/2) > , now differentiating this x2 i get a(t) i believe. Since the only force acting on the vehicle is friction, and this opposes the net...

Ah yea I realized that before and made the correction but thanks. What would x(t) be? I have an answer but its so long I am having a hard time thinking its right.

I think i might have made a mistake getting x(t) and y(t). I integrated ds from 0 to x so I had arc length as function of x, s(x) and then set s(x) = 1/2 *4.8*t^2 and solved for x. as far as I know this would be x(t) which i could use in my parametrization of the curve r(t) but this function...

Hmm okay. I have y(t) and x(t) now so I have r(t) = < x(t), y(t) > . Only thing is that these vectors are getting really complicated to the point i can only work with them in maple, and most of my class has never even seen vector calculus so I am starting to think there has to be a much...

Thanks for the replies. Still a little confused. The question is asking for the x position of the vehicle, not the distance covered along the path so would I still need to use arc length? I think what I am getting confused about is direction of the friction force. Am I wrong to assume that...

Ah yea my bad, the path is y(x) = 0.2 x^3/2 and the speed is a function of time

[Mentors note: Thread moved from the Classical Physics forum after it had been replied to, hence the lack of a homework template] Hey I have been trying to solve this problem for the last few days with no luck. Question: a car starts from rest at the origin and travels along the path given by...

Makes sense thanks.

Homework Statement Suppose (## a_n ##) is a sequence and let l\in\mathbb R. Let us say that (## a_n ##) is "super convergent" to ##l## if there exists N\in\mathbb N such that for every ε>0 we have ##n \geq N## ⇒ |(## a_n - l##|<ε . Show that if (## a_n ##) super converges to l then (## a_n...

Ok thanks I am pretty sure I got it now.

ok I'm able to understand most of this. I am a little confused how you changed n!/(n-k)! into that product but i can see that it makes sense. Isn't k=0 just one case though? Wouldn't i still need to prove somehow that the inequality holds for k>0 but still k<n?

Thanks for the replies. I tried playing around with these for an hour this morning. When trying to prove that equivalent statement, Its obvious that its true but I still don't know how to "prove" it. Leaves me in the same situation as before just allows me to cancel a factor of 1/k! from...

Homework Statement its the second one. let n∈ℕ \ 0 and k∈ℕ show that (n choose k) 1/n^k <= 1/k! Homework Equations axioms of ordered fields? The Attempt at a Solution [/B]i have been working on this all afternoon. I know 0<k<n since its a requirement for (n choose k). I've tried...

No not in those calculations but the next question was to calculate the induced current in the loop so I used it then. Was I supposed to use it in the first part too?