Freefall acceleration
If you throw an object up or down, the object accelerates downward at a constant freefall acceleration a = g.
Near the earth's surface g = 9.8 m/s^{2}
= 32 ft/s^{2}
^{Note g is a positive quantity.}
Equation  Freefall
acceleration
a → g x, x_{0} → y, y_{0}

Question:
Ahmed tossed a ball up along the yaxis
with initial speed 10 m/s.
(a) What is the acceleration of the ball at the highest point when the ball speed is zero?
(b) How long does the ball take to reach its maximum height?
(c) What is the ball maximum height?
(d) What is the displacement of ball when it comes back to Ahmed's hand?