Question

An object is launched into the air. The projectile motion of the object can be modeled using the function h(t) = –16t2 + 72t + 5, where t is the time in seconds since the launch and h(t) represents the height in feet of the object after t seconds. What is true about the projectile motion of this object? Check all that apply.

Answer 1

A: The initial height is 5 feet.
C: The object will hit the ground after approximately 4.57 seconds.

Answer 2

Explanation:

Given that an object is launched into the air. The projectile motion of the object can be modeled using the function

`h(t) = –16t^2 + 72t + 5,`

h(0) = 5

i.e. initial height =5

h'(t)= -32t+72

Hence velocity =0 when t = 9/4=2.25 seconds

After 2.25 seconds it will start coming down

Maximum height = h(2.25) = -16(2.25)^4+72(2.25_+5

= -81+162+5

=86