A small rock is released from rest at the edge of a cliff that is above a flat valley…
PHYSICS · Multi-part · A Level · Physics · Mechanics and materials · Mechanics and materials
Problem
A small rock is released from rest at the edge of a cliff that is 80m above a flat valley floor. Air resistance is negligible, and the downward acceleration of the rock remains constant at g=9.8m/s2.
(a) Calculate the time it takes the rock to reach the valley floor.
(b) Determine the magnitude of the rock’s velocity just before impact with the ground.
(c) Compute the rock’s average speed for the entire fall.
(d) Without performing additional calculations, explain how the graph of velocity versus time for this motion could be used to verify your answers to parts (a) and (b).