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3 years ago

A kid throws a ball from a tower 45 meters tall how fast is the ball going when it hits the ground?

Physics

1 answer:

IRISSAK [1]3 years ago

8 0

Answer:

29.69 m/s

Explanation:

From the question given above, the following data were obtained:

Height (h) = 45 m

Velocity (v) =...?

Next, we shall determine the time taken for the ball to get to the ground. This can be obtained as follow:

Height (h) = 45 m

Acceleration due to gravity (g) = 9.8 m/s²

Time (t) =?

h = ½gt²

45 = ½ × 9.8 × t²

45 = 4.9 × t²

Divide both side by 4.9

t² = 45/4.9

Take the square root of both side

t = √(45/4.9)

t = 3.03 s

Finally, we shall determine the velocity with which the ball hits the ground. This is illustrated below:

Initial velocity (u) = 0 m/s

Acceleration due to gravity (g) = 9.8 m/s²

Time (t) = 3.03 s

Final velocity (v) =.?

v = u + gt

v = 0 + (9.8 × 3.03)

v = 0 + 29.694

v = 29.694 ≈ 29.69 m/s

Therefore, the ball hits the ground with a velocity of 29.69 m/s.

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