Do you not understand how to solve for the answer?
Answer:
The time is 1.8s
Explanation:
The ball droped, will freely fall under gravity.
Hence we use free fall formula to calculate the time by the ball to hit the ground

Where h is the height from which the ball is droped, g is the acceleration due to gravity that acted on the ball, and t is the time taken by the ball to hit the ground.
From the question,
h=16m
Also, let take

By substitution we obtain,


Diving through by 9.8


square root both sides, we obtain


Since this a position vs time graph, the velocity will be the slope of the line.
(5-3) / (3-0)
2/3 m/s
.6666 m/s
Explanation:
ride. You estimate the radius of thebig wheel to be 15 {\rm m}, and you use your watch tofind that each loop around takes 25 {\rm s}.a.What is your speed