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Mazyrski [523]
3 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
Physics
1 answer:
Sedaia [141]3 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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Answer:

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I(x) = k  \int_{0}^{6}a^(5)  da ×  \int_{0}^{\pi/2}  (1-cos2θ)/2 dθ

I(x)  = k ({r}^{6}/6)^(5)_0 ×  {θ/2 - sin2θ/4}^{\pi /2}_0

I(x)  = k × ({6}^{6}/6) × (  {\pi /4} - sin\pi /4)

I(x)  = k ×  ({6}^{5}) ×   {\pi /4}

I(x)  = 1444×k ×{\pi}    .....................1

and we can say I(x) = I(y)   by the symmetry rule

and here I(o) will be  I(x) + I(y) i.e

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