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Finding the speed of a metal ball

  1. May 17, 2009 #1
    alright, so here's my question that i have to answer:
    "A ball of mass .500kg is rolling across a table top with a speed of 5.00 m/s. When the ball reaches the edge of the table, it rolls down a frictionless incline onto the floor 1.00 meter below (without bouncing). What is the speed of the ball when it reaches the floor (just before it touches the floor)?"

    I use the equation PEf + KEf = PEi + KEi and then get KEf = PEi, which then leads to
    .5mv^2 = mgh
    From here, I'm stuck. Since the ramp is frictionless, does the ball accelerate the same as it would if it was dropped? And, how would I add in the initial speed of 5.00 m/s?
     
  2. jcsd
  3. May 17, 2009 #2

    Doc Al

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    Staff: Mentor

    But KEi ≠ 0.
    No, it slides down the incline.
    That speed will be reflected in KEi.
     
  4. May 17, 2009 #3
    ok so then i would change my equation to KEf = PEi + KEi, and then from there use the equation KEf = .5mv^2 to solve for the velocity (speed), right?
     
  5. May 17, 2009 #4

    Doc Al

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    Staff: Mentor

    Right.
     
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