SIMPLIFIED: "3.7: Free Fall"

Article Link: https://phys.libretexts.org/Bookshelves/University_Physics/University_Physics_(OpenStax)/Book%3A_University_Physics_I_-_Mechanics_Sound_Oscillations_and_Waves_(OpenStax)/03%3A_Motion_Along_a_Straight_Line/3.07%3A_Free_Fall

Note: The above image was taken from the original article.

This article is all about free fall. Essentially, if an object is in free fall, that means that the force of gravity is the ONLY force acting on the object. For a beginner physics class, we need to assume that air resistance is negligible (negligible means pretend it does not exist). On Earth, the acceleration due to the force of gravity is 9.8 meters per second squared. 

Now, let’s use this example to describe free fall. Let’s say you drop a bowling ball and a piece of paper from the same height. Which one do you think is going to fall onto the ground first? Many people will say the bowling ball, and they would be absolutely correct. Now, why is that? It is because of air resistance. Air resistance causes the piece of paper to fall slower than the bowling ball. However, we just mentioned in the previous paragraph that when studying free fall, we assume air resistance does not exist. Therefore, if we assume air resistance does not exist, then the bowling ball and the piece of paper will actually hit the ground at the exact same time. This is because they start from the same height, and the only force exerted on them is the force of gravity, meaning their acceleration to the ground is the same. 

If you want to learn more about free fall, you can search up videos on Youtube where scientists test this concept by dropping both a bowling ball and a piece of paper from the same height in a room where there is basically zero air. This makes sure that there is no air resistance, and shockingly, you will find that the bowling ball and the piece of paper hit the ground at the exact same time. This experiment can also be done with a feather or literally anything.