Practice – Solve problems involving falling bodies
Questions :
A marble is thrown horizontally with a speed of 15 m/s from the top of a building. When it strikes the ground, the marble has a velocity that makes an angle of 65º with the horizontal. From what height above the ground was the marble thrown?
Suppose the water at the top of Niagara Falls has a horizontal speed of 2.7 m/s just before it cascades over the edge of the falls. At what vertical distance below the edge does the velocity vector of the water point downward at a 75º angle below the horizontal?
A diver runs horizontally with a speed of 1.20 m/s off a platform that is 10.0 m above the water. What is his speed just before striking the water?
A ball is thrown horizontally from a point 100 m above the ground with a speed of 20 m/s. Find (a) the time it takes to reach the ground, (b) the horizontal distance it travels before reaching the ground, (c) the velocity (direction and magnitude) with which it strikes the ground.
A person standing on the top of a cliff 171 ft high has to throw a ball to his friend standing on the ground 228 ft horizontally away. If he throws the ball directly aiming at the friend with a speed of 1.50 ft/s, how short will the packet fall?
Explanations :
Height = 53m
5.2 m below the edge.
14.1 m/s
(a) Time taken to reach the ground = 4.51 s
(b) Horizontal distance travelled by the ball = 90 m.
c) Final velocity is 48.42 m/s at 66 degrees.
The ball will fall short by 192.19 ft.