Physics Review

Below shows the basic physics principle that two balls of differing mass hit the ground at the same time if only gravity is acting

The values are purposefully exaggerated for illusion and gravity is default -9.8 mps. An interesting simulation with gravity can be found here.

However if drag is added ...

or a wind node to simulate air resistance

Below are the network view of drag node and wind node:

Adjusting more of the physical properties such as bounce, friction as well as mass and ensuring the size of your object is to scale will help ensure a more realistic simulation. Below the drag is reduced (default is too high) as well as bounce adjusted along with mass.