If it takes 3 s for a ball to strike the ground when it is released from rest, determine the height in meters of the building from which it was released. Also, what is the velocity of the ball when it strikes the ground?

#### Solution:

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To figure out the height of the building, we will use the following kinematics equation:

(Where s_2 is final displacement, s_1 is initial displacement, v_1 is initial velocity, t is time, and a_c is constant acceleration)

From the question, we know the following:

v_1=0 m/s

a_c=9.81 m/s^2

t=3 s

We will substitute these values into our equation.

s_2=0+0+\dfrac{1}{2}(9.81)(3^2)

s_2=44.1 m

To figure out the velocity of the ball as it hits the ground, we will use the following equation:

(Where v_2 is final velocity, v_1 is initial velocity, a_c is constant acceleration and t is time)

As before, we will substitute the values we know into the equation:

v_2=0+9.81(3)

v_2=29.4 m/s

#### Final Answers:

Velocity of ball before impact = 29.4 m/s