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Expressing speed with variables

  1. Feb 18, 2008 #1
    1. The problem statement, all variables and given/known data
    A child's toy consists of a block that attaches to a table with a suction cup, a spring connected to that block, a ball, and a launching ramp. The spring has a spring constant k, the ball has a massm , and the ramp rises a height y above the table, the surface of which is a height H above the floor.

    Initially, the spring rests at its equilibrium length. The spring then is compressed a distance s, where the ball is held at rest. The ball is then released, launching it up the ramp. When the ball leaves the launching ramp its velocity vector makes an angle with respect to the horizontal.

    Throughout this problem, ignore friction and air resistance.

    2. Relevant equations

    The first problem told me to calculate the speed of the ball when it leaves the launching ramp.

    I got sqrt((ks^2)-2(mgy))/m
    This was correct but on the next problem it is asking me with what speed will the ball hit the floor? All of this is in terms of k,s,m,g,y,or H

    I have no idea where to start. My teacher does this to us every week without teaching us a thing
  2. jcsd
  3. Feb 18, 2008 #2
    Well, you know m, g, and h right? That should give you a bit to get started on. You shouldn't have to concern yourself with the speed at which it comes off of the inclined plane. You might want to look at more of the theory behind the problem that just the calculations.

    hope this helps somewhat
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