Question

Syyedah throws a baseball with an initial velocity of 30 meters per second from a roof at an initial height of 75 meters. Write an equation to model this scenario. How long does it take the ball to reach the ground? Use algebra to find your answer. (5 pts)

Answer 1

Initial velocity: v o = 30 m/s
h = 75 m
h = v o * t + g * t² / 2
75 = 30 · t + 9.8 · t² / 2
75 = 30 t + 4.9 t²
An equation is: y = 4.9 t² + 30 t - 75
4.9 t² + 30 t - 75 = 0
$t_{12}= \frac{-30+/- \sqrt{900+1470} }{9.8}= \\ =\frac{-30+48.68}{9.8}$
t = 1.9 s