An object is launched from a launching pad 208 ft. above the ground at a velocity of 192ft/sec. what is the maximum height reached by the rocket?

Respuesta :

Answer:

The maximum height is 784 feet

Step-by-step explanation:

In this problem we use the kinematic equation of the height h of an object as a function of time

[tex]h(t) = -16t ^ 2 + v_0t + h_0[/tex]

Where [tex]v_0[/tex] is the initial velocity and [tex]h_0[/tex] is the initial height.

We know that

[tex]v_0 = 192\ \frac{ft}{sec}[/tex]

[tex]h_0 = 208\ ft.[/tex]

Then the equation of the height is:

[tex]h(t) = -16t ^ 2 + 192t +208[/tex]

For a quadratic function of the form [tex]ax ^ 2 + bx + c[/tex]

where [tex]a <0[/tex]

the maximum height of the function is at its vertex.

The vertice is

[tex]x = -\frac{b}{2a}\\\\y = f(\frac{-b}{2a})[/tex]

In this case

[tex]a = -16\\b = 192\\c = 208[/tex]

Then the vertice is:

[tex]t = -\frac{192}{2(-16)}\\\\t = 6\ sec[/tex]

Now we calculate h (6)

[tex]h(6) = -16(6) ^ 2 +192(6) +208\\\\h(6) = 784\ feet[/tex]

The maximum height is 784 feet