College

We appreciate your visit to 2 If a toy rocket is launched vertically upward from ground level with an initial velocity of tex 128 tex feet per second then its. This page offers clear insights and highlights the essential aspects of the topic. Our goal is to provide a helpful and engaging learning experience. Explore the content and find the answers you need!

2. If a toy rocket is launched vertically upward from ground level with an initial velocity of [tex]128[/tex] feet per second, then its height [tex]h[/tex], after [tex]t[/tex] seconds, is given by the equation [tex]h(t) = -16t^2 + 128t[/tex] (air resistance is neglected).

a. How long will it take the rocket to hit its maximum height?

b. What is the maximum height?

c. How long did it take for the rocket to reach the ground?

Answer :

Sure! Let's solve the problem step by step:

We have the function for the height of a toy rocket given by [tex]\( h(t) = -16t^2 + 128t \)[/tex], where [tex]\( t \)[/tex] is the time in seconds, and [tex]\( h(t) \)[/tex] is the height in feet.

### a. Time to reach maximum height:
To find the time at which the rocket reaches its maximum height, we need to find the vertex of the parabola described by the quadratic equation. The formula to find the time at which the maximum height is reached for a quadratic [tex]\( at^2 + bt + c \)[/tex] is:

[tex]\[ t = -\frac{b}{2a} \][/tex]

Here, [tex]\( a = -16 \)[/tex] and [tex]\( b = 128 \)[/tex].

[tex]\[ t = -\frac{128}{2 \times -16} = 4 \text{ seconds} \][/tex]

### b. Maximum height:
To find the maximum height, we substitute the value of [tex]\( t \)[/tex] from above into the height equation [tex]\( h(t) \)[/tex].

[tex]\[ h(4) = -16(4)^2 + 128(4) \][/tex]

[tex]\[ h(4) = -16 \times 16 + 128 \times 4 \][/tex]

[tex]\[ h(4) = -256 + 512 \][/tex]

[tex]\[ h(4) = 256 \text{ feet} \][/tex]

### c. Time to reach the ground:
The rocket reaches the ground when its height is 0, so we need to solve the equation:

[tex]\[ -16t^2 + 128t = 0 \][/tex]

Factor the equation:

[tex]\[ t(-16t + 128) = 0 \][/tex]

This gives us two solutions:

1. [tex]\( t = 0 \)[/tex] (the time at launch)
2. [tex]\( -16t + 128 = 0 \)[/tex]

Solving [tex]\( -16t + 128 = 0 \)[/tex]:

[tex]\[ 16t = 128 \][/tex]

[tex]\[ t = \frac{128}{16} = 8 \text{ seconds} \][/tex]

So the rocket reaches the ground after 8 seconds.

In summary:

- The rocket takes 4 seconds to reach its maximum height.
- The maximum height is 256 feet.
- The rocket reaches the ground after 8 seconds.

Thanks for taking the time to read 2 If a toy rocket is launched vertically upward from ground level with an initial velocity of tex 128 tex feet per second then its. We hope the insights shared have been valuable and enhanced your understanding of the topic. Don�t hesitate to browse our website for more informative and engaging content!

Rewritten by : Barada