A rock is projected from the edge of the top of
a building with an initial velocity of 16.3 m/s
at an angle of 39
◦
above the horizontal. The
rock strikes the ground a horizontal distance
of 90 m from the base of the building.
The acceleration of gravity is 9.8 m/s
2.
Assume: The ground is level and that the
side of the building is vertical. Neglect air
friction.
What is the horizontal component of the
rock’s velocity when it strikes the ground?
Answer in units of m/s