Physics
posted by Mike .
My midterm is tomorrow and I have a couple questions that I need to study. Ive tried and tried and cannot figure these out.
1) A ball is dropped from a roof and takes 3.0s to reach the ground. Calculate the elevation of the roof above the ground in meters. (neglect air resistance)
2) A car with a mass of 1500kg changes its speed from 10.0 m/s to 30.0 m/s during a 10.0s interval. Calculate the net average force acting on the car during the 10.0sinterval.

1) d= 1/2 a t^2 solve for t.
2) a= deltaV/time
but force= m*a = m * above.
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