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Homework Help: Find the velocity of the ball

  1. Nov 30, 2004 #1
    I am stuck on this problem:

    A ball with a mass of M is on a frictionless curved track with a radius of R. The track sits atop a table that has height of H. Solve the following in terms of R,g,H, and M.
    a) the velocity of the ball
    b) the time it takes to hit the floor
    c) the distance D the ball lands from the base of the table
    d)the total amount of energy the ball has when it strikes the floor

    Here are my answers, are these correct.
    a) v= sqrt(2gH) ???
    b) t=sqrt(2gh)/g ???
    d) would i add 1/2mv^2 + MgR+MgH ???
    Last edited: Nov 30, 2004
  2. jcsd
  3. Nov 30, 2004 #2

    James R

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    You've told us the track is on the table, and the ball is on the track. What's this about the ball hitting the floor? And the velocity could be anything, from the information you have given.
  4. Nov 30, 2004 #3
    I have attached a diagram to show what I am trying to solve for, and the velocity is as the ball leaves the table.

    Attached Files:

  5. Nov 30, 2004 #4
    Ive tried to work out the problem , can anyone see if these answers are correct.
    c)H+ R =distance
    d)mgh=total energy

    Last edited: Nov 30, 2004
  6. Dec 7, 2004 #5

    James R

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    Assuming it is released from rest at the top of the track, and the track is frictionless, the speed as it leaves the track will be sqrt(2gR).

    Your answer is correct.

    Answer is:


    Answer is mg(H + R), taking the zero of potential energy to be floor level.
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