During a practice match, a softball pitcher threw a ball. The height of the throw can be modelled by the equation h=−16t2+24t+1, where h = height in feet and t = time in seconds. How long does it take for the ball to reach a height of 6 feet for the first time?
0.25,1.25 secs
Given height = 6
⇒−16t2+24t+1=6
⇒16t2−24t+5=0
⇒(4t−1)(4t−5)=0
t=14,54 or 0.25, 1.25
It takes 0.25 secs to first reach a height of 6 feet. After 1.25 secs of being thrown, the ball again reaches a height of 6 feet from the ground because of free fall.