Question

Mr. Harden's class decides to perform an experiment to determine how long it takes different objects to hit the floor when dropped from a desk. The class dropped three balls from a desk, one weighing 2 pounds, one weighing 4 pounds, and one weighing six pounds. It took them all the same amount of time to hit the floor. After evaluating these results, you predict that a 10 pound ball will take
A) more time to hit the floor
B) less time to hit the floor
C) about the same amount of time to hit the floor
D) an unknown amount of time to hit the floor

Answer 1

C. About the same amount of time to hit the floor

Answer 2

Answer:

In this problem we are talking about objects in Free Fall, what does it mean?

Objects that are dropped from a certain height and fall to the ground with the acceleration of the gravity $g$ (in this case we are on Earth, so the gravity value is $9.8\frac{m}{s^{2}}$).

According to the experiments done since ancient times and currently verified, in vacuum (this means there is not air or any fluid), all objects in free fall experience the same acceleration, which is the acceleration of gravity.

Note that these objects experience the acceleration of gravity regardless of their mass

In other words, if we have two objects with different masses, A is greater than B; both will fall to the ground at the same time with the same gravity acceleration.

Now, in the real life we have air on Earth, and may have air resistance. In this case the greater object A will fall to the ground before the lesser object B, because B was more affected by air resistance than A.

Nevertheless, if the air resistance is too small that we can approximate it to zero in the calculations, in free fall the objects will accelerate downwards at $9.8\frac{m}{s^{2}}$ and hit the ground at approximately the same time.

Then, the answer to this question is C:

The 10 pound ball will take about the same amount of time to hit the floor