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3 years ago

The Sears Tower in Chicago is approximately 444 m tall Suppose a book

Physics

1 answer:

Reptile [31]3 years ago

4 0

Answer:

A. 66.0 m/s downwards

Explanation:

The Tower has a height of 444m

The book is dropped ,finding the velocity of the book 222m above the ground, means the book will be on air for a height of 222 m .

Apply the formula for free fall in a horizontal projection as;

h= u²×sin²∅ /2g where

h= maximum height =222m

g= acceleration due to gravity =9.81 m/s²

∅ = projectile angle = 0

u = velocity of the book

Applying the formula as ;

h= u²×sin²∅ /2g

222 = u²/2*9.81

222*19.62 = u²

4355.64 = u²

√4355.64 = u

65.99 m/s = u

66 m/s downwards

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