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3 years ago

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A ball is thrown straight down with a speed of Va2.00 from a building 40.00 meters high. How much S time passes before the ball

reaches the ground? a.) -3.07s b.) - 2.46 s c.) =2.66s d.) =9.89s e.) None of the above.A ball is thrown straight down with a speed of Va2.00 from a building 40.00 meters high. How much S time passes before the ball reaches the ground? a.) -3.07s b.) - 2.46 s c.) =2.66s d.) =9.89s e.) None of the above.

1 answer:

-Dominant- [34]3 years ago

6 0

Answer:

Option C is the correct answer.

Explanation:

Considering vertical motion of ball:-

Initial velocity, u = 2 m/s

Acceleration , a = 9.81 m/s²

Displacement, s = 40 m

We have equation of motion s= ut + 0.5 at²

Substituting

s= ut + 0.5 at²

40 = 2 x t + 0.5 x 9.81 x t²

4.9t² + 2t - 40 = 0

t = 2.66 s or t = -3.06 s

So, time is 2.66 s.

Option C is the correct answer.

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