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A ball falls down from a cliff 0.86 meters in height, and lands 1.4 meters away from the bottom of the cliff. Find the velocity of which the ball left the cliff and the direction of the ball's velocity before it hit the ground.

User Vana
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1 Answer

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Answer:

The velocity of the ball before it hit the ground was (3.59 m/s, -3.32 m/s) in the horizontal and vertical direction

Step-by-step explanation:

The velocity of the ball can be calculated using the equation of motion:

v^2 = u^2 + 2as,

where

u = initial velocity,

v = final velocity,

a = acceleration due to gravity (9.8 m/s^2),

s = vertical height fallen (0.86 m).

Solving for u:

u = sqrt(v^2 - 2as)

We know the final velocity, v = 0 (the ball lands on the ground and stops), so

u = sqrt(2as) = sqrt(2 * 9.8 * 0.86) = 3.32 m/s.

The direction of the velocity before it hit the ground can be determined using horizontal distance traveled and time of flight.

The time of flight, t, can be found using:

t = sqrt(2s/a) = sqrt(2 * 0.86 / 9.8) = 0.39 s.

The horizontal velocity, vx, can be found using:

vx = d / t = 1.4 / 0.39 = 3.59 m/s.

User Gkatzioura
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