SOLUTION: an object that is projected straight downward with an initial velocity of v per second travels a distance s = vt + 9t^2, where t=time in seconds. if dan is standing on a balcony 17

Question 452889: an object that is projected straight downward with an initial velocity of v per second travels a distance s = vt + 9t^2, where t=time in seconds. if dan is standing on a balcony 176 feet above the ground and throws a penny straight downward with an intial velocity of 8 feet per second, in how many seconds will it reach the ground?
Answer by lwsshak3(11628) (Show Source): You can put this solution on YOUR website!
an object that is projected straight downward with an initial velocity of v per second travels a distance s = vt + 9t^2, where t=time in seconds. if dan is standing on a balcony 176 feet above the ground and throws a penny straight downward with an intial velocity of 8 feet per second, in how many seconds will it reach the ground?
..
When the object reaches the ground it will have traveled 176 feet
176=8t+9t^2
9t^2+8t-176=0
solve by following quadratic formula
..

..
a=9, b=8, c=-176
t=[-8�sqrt(8^2-4*9*-176)]/2*9
t=[-8�sqrt(6400)]/18
t=(-8�80)/18
t=72/18=4 sec
or
t=-88/18=-4.88..(reject, time≥0)
ans:
The object wll reach the ground in 4 seconds.
RELATED QUESTIONS
An object that is projected straight downward with initial velocity v feet per second... (answered by ankor@dixie-net.com)

An object that is projected straight downward with initial velocity v feet per second... (answered by solver91311)

an object that is projected straight downward with initial velocity, v feet per second... (answered by lwsshak3)

Anobject that is projected straight downward with initial velocity v feet per square... (answered by RAY100)

i don't really know which category this goes under but here goes nothing... an object... (answered by ankor@dixie-net.com)

oky so im practicig for the cst by using the cst release qestion but im havng trouble... (answered by mananth)

An object that is projected straight downward with initial velocity of v feet per second... (answered by nerdybill,josmiceli)

I'm having a little trouble with this problem: Brent throws an object downward with... (answered by Alan3354)

the height of an object is given by s=-9t^2+vt+s0 where v is the initial velocity and s0... (answered by ikleyn)