Arturo O. answered • 03/08/18
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F = ma
a = (vf - vi)/t = [(0 - 3.0)m/s]/(2 s) = -1.5 m/s2
F = ma = (850 kg)(-1.5 m/s2) = -1275 N
The minus sign means the force opposes the direction of motion.
Arturo O.
This is a 2nd law situation. That is why I started by writing
F = ma.
The even braking of the elevator means both the force and the acceleration are constant over the time it takes to bring the speed down to zero.
And you are welcome, Thomas.
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03/08/18
Thomas M.
03/08/18