Question

Tom throws a Frisbee into the air from a height of 4 feet with

an initial vertical velocity of 64 feet per second. Use the vertical
motion model, h = -16t2 + vt +s, where v is the initial velocity in
feet/second and s is the height in feet, to calculate the
maximum height of the frisbee. Round your answer to the
nearest tenth if necessary.
Maximum height: — feet
Enter the answer
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Answer 1

68 feet

Explanation:

Vertical motion model:

h = -16t² + vt + s

Given v = 64 and s = 4:

h = -16t² + 64t + 4

This is a parabola. The maximum of a parabola is at the vertex.

For y = ax² + bx + c, the vertex is at x = -b/(2a).

Therefore, the time to reach the maximum height is:

t = -64 / (2 × -16)

t = 2

And the maximum height is:

h = -16(2)² + 64(2) + 4

h = 68

So the Frisbee reaches a maximum height of 68 feet.