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mariarad [96]
3 years ago
12

A stone is dropped from the edge of a roof, and hits the ground with a velocity of -180 feet per second. How high (in feet) is t

he roof? Note: the acceleration of an object due to earth's gravity is 32 f t sec 2
Physics
1 answer:
Neko [114]3 years ago
6 0

Answer:

d = 506.25 ft

Explanation:

As we know by kinematics that

v_f^2 - v_i^2 = 2 a d

here we know that initially the stone is dropped from rest from the edge of the roof

so here initial speed will be zero

now we have

v_i = 0

also the acceleration of the stone is due to gravity which is given as

g = 32 ft/s^2

now we have

v_f = 180 ft/s

so from above equation

180^2 - 0 = 2(32)d

d = 506.25 ft

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          v = 5.25 10⁻¹  1 / √r

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