WAEC Physics 2015 Paper

Concept:Archimedes' principle states that the upward buoyant force on a floating object equals the weight of the fluid displaced by the object.Explanation:When an object is placed in a fluid, it settles until the upward force exactly balances its downward weight.This condition is written as $F_b = W_{\text{object}} = W_{\text{fluid displaced}}$.The relevant quantity is the weight of the displaced fluid, not its volume, mass, or density alone.Density and volume combine to give mass, and mass times $g$ gives weight.So, a floating object displaces a fluid whose weight is equal to the object's own weight.This matches the option that refers to the weight of the fluid in which it floats.Answer:C. weight of fluid in which it floats.