# Homework Help: Terminal Velocity & Mass

1. Nov 26, 2012

### Nubcake

If two people of different masses say 50kg and 100kg were to suddenly jump off a building , why would the person with more mass attain a higher terminal velocity? I thought mass was irrelevant. I missed 1 lesson on this in class but this part I don't understand properly. If they were the same shape would the person with mass 100kg still have a greater terminal velocity?

Edit: A object reaches terminal velocity when the drag force is equal to the weight of the object; so am I right to say that W=mg comes into this and the person with more mass has more weight so more drag is needed to reach terminal velocity?

2. Nov 26, 2012

### lewando

Weight is certainly a big determinant of terminal velocity. Think how fast an air-filled balloon reaches t.v. (and how slow it is) compared with a bowling ball of same size. Shape is also a factor: a teardrop-shaped object vs a parachute-shaped object of the same mass will have different terminal velocities.

3. Nov 26, 2012

### Staff: Mentor

Mass is only irrelevant if the only force is gravity. When a drag force is also present, unless the drag force is directly proportional to mass, the terminal velocity will depend on mass.