Posted by **steph** on Thursday, November 10, 2011 at 8:19pm.

Physics: a ball is thrown vertically upward with an initial velocity of 80 feet per second. the distance (in feet) of the ball from the ground after t seconds if s=80t-16tt^2

a) draw the illustration

b) for what time interval is the ball more than 96 feet above the ground?

c) what is the maximum height of the ball?

d) after how many seconds does the ball reach the maximum height?

- pre-calc -
**Reiny**, Thursday, November 10, 2011 at 9:56pm
b)

80t - 16t^2 > 96

16t^2 - 80t + 96 < 0

t^2 - 5t + 6 < 0

(t-2)(t-3) < 0

so the ball is higher than 96 for

2 < t < 3, that is, between 2 and 3 seconds

c) s = -16(t^2 - 5t ** + 25/4 - 25/4**)

= -16(t-5/2)^2 + 100

I will leave it up to you to interpret that result.

- pre-calc -
**steph**, Thursday, November 10, 2011 at 10:09pm
another great help!

## Answer This Question

## Related Questions

- Pre-Calc - ball thrown vertically upward with an initial velocity of 80 ft per ...
- Precalculos - A ball is thrown vertically upward with an initial velocity of 96 ...
- Pre-Calculus - A ball is thrown vertically upward with an initial velocity of 64...
- math - a ball is thrown vertically upward from the top of a building 96 feet ...
- Math- - A ball is thrown vertically upward with an initial velocity of 96 feet ...
- Algebra - THe function h(t)=-16t^2+v0t+h0 describes the height in feet above the...
- Algebra - THe function h(t)=-16t^2+v0t+h0 describes the height in feet above the...
- physics - A ball is thrown vertically upward from the ground with an initial ...
- Calculus - Use a(t)=-32 ft/second squared as the acceleration due to gravity. A ...
- calculus - A ball is thrown vertically upward with an initial velocity of 128 ...

More Related Questions