h = 0.5g*t^2 = = 4.9*4^2 = 78.4 m.
Y = Yo + g*t = 0 + 9.8*4 = 39.2 m/s.
V = Xo + Y = 20 + 39.2i = 44m/s[63o].
d = Xo*t = 20 * 4 = 80 m. from base of bldg.
A ball is thrown horizontally from the building roof at a speed of 20 m/s. Takes ball 4 seconds to reach the ground. How tall is building?
What is the ball’s speed and direction as it contacts the ground?
How far from the base of the building does the ball land?
Use conservation of energy to determine the speed of the ball as it contacts the ground.
1 answer