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Homework Help: Velocity of Ball on a Decline Ramp

  1. Nov 6, 2008 #1
    My physics teacher gave us this challenge question as homework, and basically the entire class is struggling with it. Guidance would be much appreciated.
    A ball is released, with an initial velocity of 0, on a 1 m long ramp. The ramp is set up on a table, approximately .75 m above the ground, and we have to figure out where the ball will land on the floor. Here are all of the known values we have:

    Initial Velocity of ball = 0 m/s
    Length of Ramp: 1 m
    Angle of Ramp Relative to the Table: 13o
    Max Height of the Ramp: 22 cm
    Vertical Distance from the Floor to the Table: 75 cm

    Variables I am trying to find:
    ?? = Total Velocity of the Ball at the end of the ramp
    ?? = Vertical and Horizontal Velocities of the Ball at the end of the ramp
    ?? = Time it takes for the Ball to move all the way down the ramp
    ?? = How far away the ball would land away from the table (The system is set up so that the ball would not bounce off the table after falling off the ramp, it would go directly to the floor)

    My partner and I tried many equations, but in all of them we were missing key variables, such as the mass of the ball.

    As I said above, we tried many things, but in the end we just ended up needing another variable that was not given to us.
  2. jcsd
  3. Nov 6, 2008 #2
    Have you learned conservation of energy principles (particularly [tex]mgh=\frac{1}{2}mv^{2}[/tex]) yet? You can use that to solve for the velocity of the ball.
  4. Nov 6, 2008 #3
    A good starting point will be to consider that momentum is conserved. That means that potential energy at the start = kinetic energy at the end.

    Potential energy = mgh, kinetic energy = 0.5*m*v^2
  5. Nov 7, 2008 #4
    Is the "m" in those equations the mass? Because if so, we were not given the mass, so I would have to make an estimate.
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