(adsbygoogle = window.adsbygoogle || []).push({}); Hey all, I really need help with this homework. Any help would be appreciated(FIXED)

Problem: Ball of mass m hangs on a string of length L straight down from a cart of mass

M standing on horizontal rails. The cart can move along the rails without friction.

While the cart is at rest, the ball is given a horizontal velocity v0, v0 < sqr(2gl) directed

along the rails.

(a) What is velocity of the ball when it reaches

its maximal elevation?

(b) What is elevation h that the ball reaches

above its original location?

First of all hello.

I am new to this forum and don't really know your ways yet, so please forgive me if I do something wrong. This problem has tormented me for days. I did all the other homework problems for this week and this is the last one. If anyone would help me solve the problem I would be forever grateful.

m = mass of the ball

M = mass of the cart

v0 = velocity given to the ball

V = velocity of the cart

theta = angle between the starting position of the string and the maximal elevation of the string

Sorry for not giving any attempts, but I really don't know where to start on this one. All i have is:

(1/2)m(v0)^2 = (1/2)mv^2 + mgh + (1/2)MV^2

mv0 = mvcos(theta) + MV

I also found center of mass, in respect to the position of the ball:

(L - mL/(M + m) = CM

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# Homework Help: Hey all, I really need help with this homework. Any help would be appreciated

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