If a 20 kg object fell to the surgace of the Earth froma height of 30 m, what would its final velocity be? (work problem from the stanpoint of linear motion)
hf=hi+vi*t- 4.9t^2
hf, vi is zero, solve for t
then
vf=vi-9.8t
To find the final velocity of the object, we can use the equations of motion. In this case, we need to find the final velocity using the information given about the mass, initial height, and gravitational acceleration.
The first equation of motion we can use is:
v^2 = u^2 + 2as
Where:
v = final velocity
u = initial velocity (which is 0 in this case)
a = acceleration due to gravity (approximately 9.8 m/s^2)
s = displacement (in this case, the initial height of 30 m)
Since the object is falling vertically downward, we can consider the displacement as negative. Therefore, s = -30 m.
Substituting the known values into the equation, we get:
v^2 = 0 + 2(-9.8)(-30)
Simplifying further:
v^2 = 2(9.8)(30)
v^2 = 588
Taking the square root of both sides:
v ≈ √588
v ≈ 24.25 m/s
Therefore, the final velocity of the 20 kg object when it reaches the surface of the Earth from a height of 30 m is approximately 24.25 m/s.