Answer: A. A ball bouncing on a sidewalk
Explanation:
S H M or Simple Harmonic motion can be described as the type of motion that repeats it self after a fixed interval of time and a restoring force acts in the direction opposite to the direction of the displacement of the object.
From the given options, option A where in a ball bounces on a sidewalk is a repeated motion in a fixed interval of time. A force always acts on the ball in the direction opposite to the displacement of the ball. Thus, it is a correct example of simple harmonic motion.
