An object floats on the surface of a fluid.For purposes of calculating the torque on it, the buoyant force is taken to act at:
A)the center of the bottom surface of the object
B)the center of gravity of the object
C)the center of gravity of the fluid that the object replaced
D)the geometric center of the object
E)none of the above

Question

Quizplus · Accepted Answer

The buoyant force always acts at the center of gravity of the fluid that the object displaced. This is known as Archimedes' principle. Therefore, the torque on the object should also be calculated using this point. Choosing any other point would result in an incorrect torque calculation.

An Object Floats on the Surface of a Fluid