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Papessa [141]
3 years ago
10

A hoodlum throws a stone vertically downward with an initial speed of 12.0 m/s from the roof of a building,30.0 m above the grou

nd. (a) how long does it take the stone to reach the ground
Physics
1 answer:
bogdanovich [222]3 years ago
8 0
S=ut +1/2at2
30=12t+1/2*10*t2
5t2+12t-30=0
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