Why does a bowling ball and a feather hit the ground at the same time when they are dropped in a vacuum?

See the explanation below.

Explanation:

This is because the vacuum chamber removes all the air contained and for this reason, there is no force that opposes the movement of the feather when falling. We must remember that the free fall equation of kinematics is not a function of the mass of an object.

where:

Vf = final velocity [m/s]

Vo = initial velocity [m/s]

g = gravity acceleration [m/s²]

t = time [s]

As we can see the mass of the object is not included in the equation.

1/0.14nm = 10^10/1.4 a lot

the answer is kevlar