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If an object is thrown vertically upward with an initial velocity of v, from an...

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kristenmarieb... | Student, Grade 10 | Valedictorian

Posted May 6, 2013 at 9:36 PM via web

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If an object is thrown vertically upward with an initial velocity of v, from an original position of s, the height h at any time t is given by: h = 16t^2 + vt + s.  (Where h and s are in feet, t is in seconds and v is in ft/sec).  

A ball is thrown upward with initial velocity of 96 ft/sec from the top of a 100 ft bridge.  Determine the time that it takes for the ball to get to a height of 200 ft from the ground. 

Round answers to two decimals, separated by a comma.

Tagged with algebra 2, math

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pramodpandey | College Teacher | Valedictorian

Posted May 7, 2013 at 3:59 AM (Answer #1)

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u= 96 ft/sec

s=100 ft  (height of the top of bridge)

h= 200 ft   (from ground)

200=16 t^2+96t+100

16t^2+96t-100=0

4t^2+24t-25=0

`t=(-24+-sqrt(24^2+4xx4xx25))/16`

`=(-24+-31.241)/16`

`t>0 therefore`

`t=7.241/16`

`=.453` sec.

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