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A man standing on top of a 30 m tall building throws a brick downwards with a velocity of 12 m/s. Determine the speed of the brick just before it hits the ground.

User Cybering
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1 Answer

13 votes

Answer:

27.1m/s

Step-by-step explanation:

Given parameters:

Height of the building = 30m

Initial velocity = 12m/s

Unknown:

Final velocity = ?

Solution:

We apply one of the kinematics equation to solve this problem:

v² = u² + 2gh

v is the final velocity

u is the initial velocity

g is the acceleration due to gravity

h is the height

v² = 12² + (2 x 9.8 x 30)

v = 27.1m/s

User Ananth
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