An old question is “Which weighs more, a pound of feathers or a pound of lead?” If the weight in pounds is the gravitational force, will a pound of feathers balance a pound of lead on opposite pans of an equal-arm balance? Explain, taking into account buoyant forces.

The buoyant force is equal to the weight of the volume of displaced fluid by the object.When the entire fluid is in equilibrium, the sum of all the force components on this fluid element is zero.

Hence, the sum of the surface forcescomponents must be an upward force equal in magnitude to the weight of the fluid inside the surface.

The density of lead makes it take up less volume than feathers. As a result, a pound of lead feels a smaller buoyant force than a pound of feathers because lead displaces less air than feathers due to their density.

So, its volume is higher than the lead,therefore, the gravitational force acting on one pound of lead and one pound of feathers is equal. As the buoyant force on lead is less than the buoyant force acting on the feathers, the net force acting downwards on the lead is greater than the net force acting on the feathers.

With a sensitive equal-arm balance, the lead will not be equal to the feathers due to their differing buoyant forces. The side carrying lead will sink since the net force on both sides is not equal.

Thus,a pound of feathers will not balance a pound of lead.