Question

A model rocket is launched upward at a speed of 128 feet per second from a platform 15 +feet above the ground. Choose a statement about the rocket's flight The rocket will reach its maximum height after 7 seconds. The rocket will reach its maximum height after 5 seconds. The maximum height that the rocket will reach is 191 feet. The maximum height that the rocket will reach is 271 feet.

Answer 1

The maximum height that the rocket will reach is 271 feet.

Explanation:

We first calculate the time, t it takes the rocket to reach maximum height from v = u - gt. Since u = initial velocity = 128 ft/s, v = velocity at maximum height = 0 ft/s and g = acceleration due to gravity = 32 ft/s².

So, v = u - gt.

t = (u - v)/g

= (128 ft/s - 0 ft/s)/32 ft/s²

= 128 ft/s ÷ 32 ft/s²

= 4 s.

We calculate the maximum height from

y - y₀ = ut - 1/2gt² where y₀ = 15 ft and all other variables are as above.

Substituting these values into the equation, we have

y - y₀ = (u - 1/2gt)t

y - 15 ft = (128 ft/s - 1/2 × 32 ft/s² × 4 s) × 4 s

y - 15 ft = (128 ft/s - 64 ft/s)4 s

y - 15 ft = 64 ft/s × 4 s

y - 15 ft = 256 ft

y = 256 ft + 15 ft

y = 271 ft

So, the maximum height that the rocket will reach is 271 feet.