If we are taking air resistance into account, when two objects of different masses are dropped, is the lighter object experiencing less acceleration in the downward direction?
Air resistance and acceleration
- Thread starter m25
- Start date
- Joined
- Feb 27, 2013
- Messages
- 3,469
- Reaction score
- 2,287
If we look at two objects that are identical except for mass we can compare.
Lets say the more massive object has mass M, and the lighter object is mass m = 0.5M.
Just looking at vertical forces. We can also state that the drag forces will be identical, since it is not based on mass, so drag force = D.
Massive
F = MA = Fd + Fg = D - Mg
Ma = D - Mg
A = (D - Mg)/M = (D/M) - g
From that calculation we know the acceleration of the lighter object is a = (D/m) - g
a = (D/m) - g = (D/0.5M) - g = (2D/M) - g
So more massive object A = (D/M) - g < a = (2D/M) - g
Therefore we know the lighter object is feeling a more positive upwards force (or less force downwards).
Since the lighter object has less downwards force, it experiences less downwards acceleration.
Lets say the more massive object has mass M, and the lighter object is mass m = 0.5M.
Just looking at vertical forces. We can also state that the drag forces will be identical, since it is not based on mass, so drag force = D.
Massive
F = MA = Fd + Fg = D - Mg
Ma = D - Mg
A = (D - Mg)/M = (D/M) - g
From that calculation we know the acceleration of the lighter object is a = (D/m) - g
a = (D/m) - g = (D/0.5M) - g = (2D/M) - g
So more massive object A = (D/M) - g < a = (2D/M) - g
Therefore we know the lighter object is feeling a more positive upwards force (or less force downwards).
Since the lighter object has less downwards force, it experiences less downwards acceleration.
Last edited:
