Falling Masses, Again

Most recent answer: 08/10/2010

Why do two objects, same size and shape but with different masses fall at the same time?
- Deliah Jade Paterson
San Francisco, CA, US
In the absence of air resistance all objects fall at the same accelerated rate. When falling in air, the force of gravity is the same and proportional to m.  Galileo figured this out a long time ago.  However, the air resistance force is proportional to the area, independent of the mass. So two extended objects with the same shape but with different masses will not fall with the same acceleration.
See the nice video of a feather and a ball bearing falling in air and in a vacuum.


(published on 08/10/2010)