Hey all, I really with this homework. Any help would be appreciated

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A user seeks assistance with a physics homework problem involving a ball and cart system. The problem requires calculating the velocity of the ball at its maximum elevation and the height it reaches above its original position after being given an initial horizontal velocity. The user expresses frustration after struggling with the problem for days and admits to not having made any attempts to solve it. Forum members emphasize the importance of showing attempts to solve the problem before receiving help. The discussion highlights the user's unfamiliarity with forum etiquette and the need for clearer communication.
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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
 
Last edited:
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spartanpol said:
1. Ball of mass m hangs on a string of length ` 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 <
p
2g`, directed
along the rails.


Homework Equations


(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.

Hello spartanpo. Welcome to PF !

You have some typos.

I am unable to make sense of your question.
 
spartanpol said:
I am new to this forum and don't really know your ways yet

Well, our ways are that you must show your attempts to solve the problem before we can help.
 
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