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stangeroo
Apr10-05, 11:18 PM
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

stangeroo
Apr14-05, 06:54 PM
bump, anyone

marlon
Apr14-05, 06:58 PM
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 + 1/2atē

where x_0 is initial position and v_0 is initial velocity
marlon