Question: How does mass affect terminal velocity when a drag force is present?

[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?

 

[lewando]

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?

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.

 

[Chestermiller]

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?

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.