Vertical motion word prob: An object is released at a height

[Third Degree]

An object is released into the air at an initial height of 6 feet and an initial velocity of 30 feet per second. The object is caught at a height of 7 feet. Use the vertical motion model, h = -16t^2 + vt + s, where h is the height, t is the time in motion, s is the initial height, and v is the initial velocity, to find how long the object is in motion.

Can anyone help me out here?? I am COMPLETELY lost.

 

[stapel]

Plug the values they gave you into the formula they gave you. Then think about what the height will be when the object stops moving (assuming it doesn't bounce). Then find the time t when the object is at that height.

Eliz.

 

[Third Degree]

Plug the values they gave you into the formula they gave you. Then think about what the height will be when the object stops moving (assuming it doesn't bounce). Then find the time t when the object is at that height.

Eliz.

I tried to reason your steps but i'm still running into some complications...
what do i do after i plug them in and 30 feet per second..do i just leave it as 30? (30t) how do i find the height...if anyone can take me a little farther on this to get me more towards the end, I'D HIGHLY APPRECIATE IT!

 

[stapel]

I tried to reason your steps but i'm still running into some complications.

It would help if you showed your work, so we could see where you are stuck.

You are given the equation. Can you find this in the exercise?

You are given definitions of each of the variables. Can you find this in the exercise? If so, then:

You are given the initial height. Can you find this in the exercise? Where does it go in the equation they gave you?

You are given the initial velocity. Can you find this in the exercise? where does it go in the equation they gave you?

You are given the height where the object is caught. Assuming it doesn't bounce, does the object stop moving at this point? (What does "caught" mean?) Can you find where "height at time t" goes in the equation they gave you?

If you could follow the above, you should now have a quadratic equation in the variable "t". Can you solve quadratic equations, or is this where you are stuck?

Please reply showing how far you have gotten in working through the steps. Thank you.

Eliz.

 

[Third Degree]

i've gotten this far and im completely stuck....

i plugged in all the values and came out with

7=-16t^2 + 30t + 6

what the heck do i do now?? anyone out there that can help me?

 

[Denis]

i've gotten this far and im completely stuck....
i plugged in all the values and came out with
7=-16t^2 + 30t + 6
what the heck do i do now?? anyone out there that can help me?

That's a simple quadratic equation, TD:
16t^2 - 30t + 1 = 0

If you don't follow that, you need your teacher.