Atrebuchet launches a projectile from ground level on a parabolic arc at a velocity of 40 feet per second. the equation h = -16t^2+40t models the projectiles height at t seconds. how long will it take for the projectile go hit it’s target on the ground?

The projectile hits the target after 2.5 seconds.

Solution:

Given, A trebuchet launches a projectile from ground level on a parabolic arc at a velocity of 40 feet per second.  

The equation h = -16t^2+40t models the projectiles height at t seconds.  

We have to find how long will it take for the projectile go hit it’s target on the ground?

Now, when the projectile hits its target on ground, its height becomes 0

neglect t = 0 as it represents initial phase of projectile.

16t = 40  

t = 2.5

Hence, the projectile hits the target after 2.5 seconds