The Boat/Rock Brainteaser ft Simone Giertz part 2/3

A body achieves terminal velocity when the force of air resistance=weight of the body
The bodies accelerate at the same rate. Heavier body implies more drag force required to achieve terminal velocity. So the heavy object needs to accelerate longer in order to achieve terminal velocity because it has more weight. Since the rate of acceleration is same for both the objects the object that had been accelerating longer achieves a greater terminal velocity