Answer:
50.2 m
Step-by-step explanation:
We can solve the problem by using the following SUVAT equation for the vertical position of the rock:

where
h is the initial height (the depth of the canyon), taking the bottom of the canyon as reference position
u = 0 is the initial velocity of the rock
t is the time
is the acceleration of gravity
When the rock reaches the bottom, t = 3.2 s and y = 0. Substituting these numbers and solving for h, we find the depth of the canyon:
