Why does the engineering design process not move smoothly from step to step, but instead goes back and forth between the steps? i know this answer, lol but i don’t know how to explain it! this

The experiment done in lab is repeated, using a ball that has unknown mass m. you plot your data in the form of f 2 versus m/l, with f in rev/s, m in kg, and l in m. your data falls close to a straight line that has slope 3.19 m/(kg · s2). use g = 9.80 m/s2 and calculate the mass m of the ball.

What kind of simple machine is a catapult?

In addition to gravity, what is the other predominant force that affects the motion of a pendulum?