A stone is thrown vertically downward from a 2.00x10^2m high cliff at an initial velocity of 5.00m/s. (a) How long does it take for the stone to reach the base of the cliff? (b) What is the stones final velocity?(adsbygoogle = window.adsbygoogle || []).push({});

a) d = vi(t)+1/2a(t)^2

200=5(t)+1/2(9.81)t^2

0= -200 + (5)t + (4.910^2

4.91(t)^2 + (5)t -200

t= -5+- sqaureroot sign (5)^2-4(4.91)(-200)

-5+- squareroot sign 25+3953 / 9.81

t=6.0s

so i used the quadratic fromula

b) vf^2=vi^2+2ad

vf^2=5^2+2(9.81)(200)

vf^2=25+19.62(200)

vf^2 = 3949

vf= 63m/s

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# Homework Help: Stone thrown question

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