How do the terminal velocity of two objects compare if they both have the same mass but one has the larger surface area

Terminal velocity is the speed at which drag force equals weight. If two objects have the same mass (and therefore the same weight), but one has a larger surface area, then the object with the larger surface area will have a lower terminal velocity.

We can show this using the equation for drag force. When drag equals weight:

W = D

mg = ½ρv²CA

Solving for v²:

v² = 2mg / (ρCA)

With m (mass), ρ (air density) and C (drag coefficient) held constant, v decreases as A increases.