A person throws a rock straight up into the air. At the moment it leaves the person's hand it is going 88 mph. When the rock reaches its peak, how fast is it going and what is the magnitude and direction of its acceleration? Ignore air drag.
2 answers
at it's peak the speed is zero, and the only acceleration is toward gravity, -9.81m/s^2
The velocity is zero at peak height, and the accleration is always -g (directed vertically downward).