Question

An object with a weight of 400 N floats in water because its weight is compensated for by an equal-magnitude upthrust force. The area of the object that the upthrust force acts on is 2.5 m^2. a) What is the force of buoyancy on this object? b) What is the magnitude of the pressure of the water on the object? *

Answer 1

Answer:

The upward buoyant force that is exerted on a body immersed in a fluid, whether partially or fully submerged, is equal to the weight of the fluid that the body displaces and acts in the upward direction at the center of mass of the displaced fluid”.

The value of thrust force is given by the Archimedes law which was discovered by Archimedes of Syracuse of Greece. When an object is partially or fully immersed in a liquid, the apparent loss of weight is equal to the weight of the liquid displaced by it.

Archimedes Principle Explanation

Archimedes Principle

If you look at the figure, the weight due to gravity is opposed by the thrust provided by the fluid. The object inside the liquid only feels the total force acting on it as the weight. Because the actual gravitational force is decreased by the liquid’s upthrust, the object feels as though its weight is reduced. The apparent weight is thus given by:

Apparent weight= Weight of object (in the air) – Thrust force (buoyancy)