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2 years ago

15

I drop a penny from the top of the tower at the front of billy jones high school and it takes 30 seconds to hit the ground calcu

late the velocity in m/s after 25 seconds of free fall

1 answer:

Sedaia [141]2 years ago

3 0

Answer:

The velocity of the penny at 25th second is, v = 245 m/s

Explanation:

Given,

The time taken by the penny to hit the ground is, t = 30 s

The initial velocity of the penny, u = 0 m/s

The velocity of the penny at 25th second, v = ?

Using the II equation of motion, the displacement is given by the formula

<em> S = ut + ½ gt²</em>

= 0 + ½ x 9.8 ( 25²)

= 3062.5 m

Using the III equations of motion

<em>v² = u² + 2gs</em>

Substituting the given values,

v² = 0 + 2 x 9.8 x 3062.5

= 60025

v = 245 m/s

Hence, the velocity of the penny at 25th second is, v = 245 m/s

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