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Homework Help: Chasing a cart down an incline

  1. Apr 10, 2005 #1
    Jill has just gotten out of her car in the grocery store parking lot. The parking lot is on a hill and is tilted 3 degrees. Fifty meters downhill from Jill, a little old lady lets go of a fully loaded shopping cart. The cart, with frictionless wheels, starts to roll straight downhill. Jill immediately starts to sprint after the cart with her top acceleration of 2 m/s^2

    How far has the cart rolled before jill catches it?

    I know you need to set two formulas equal to each other, but I dont know which formulas :cry:

    EDIT: I started off by drawing it out and taking the sin of 3 degrees, .0523 and multiplying it by 9.8 to get the acceleration of the cart, I dont know where to go from there
     
  2. jcsd
  3. Apr 14, 2005 #2
    bump, anyone
     
  4. Apr 14, 2005 #3
    the cart's acceleration is NOT 9.81 but 9.81sin(3°)

    Jill's initial position and velocity is ZERO, her acceleration is 2 + 9.81sin(3°) due to gravity also.

    For the cart : initial velocity is zero; initial position is 50 (i assume the 50m downward is along the hill and not measured horizontally)...This is all you need

    Use x = x_0 + v_0*t + 1/2at²

    where x_0 is initial position and v_0 is initial velocity
    marlon
     
    Last edited: Apr 14, 2005
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