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Viefleur [7K]
2 years ago
14

(b) A ball is thrown vertically upwards with

Physics
1 answer:
harina [27]2 years ago
6 0

Answer:

5 seconds

Explanation:

The vertical position of the ball will be given by the equation

df = do + vo t + 1/2 a t^2        df = final position  = 0  ( on the ground

                                              do = original position  ( 25 m )

                                               vo = original velocity (+ 20 m/s)

                                                a = - 10 m/s^2

So this becomes

0 = 25 + 20 t  - 1/2 (10)t^2      

  =  - 5 t^2 +20 t + 25             Use Quadratic Formula   a = -5    b=20  c = 25

                                                      to find the positive value of t = 5 seconds

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A Neglecting air resistance, a ball projected straight upward so it remains in the air for 10 seconds needs an initial speed of
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(C) is correct option.

Explanation:

Given that,

Time = 10 sec

For first half,

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3 years ago
In 1.71 minutes, a ski lift raises four skiers at constant speed to a height of 148 m. The average mass of each skier is 62.9 kg
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After reading this whole question, I feel like I've already
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