Question

When a solid is partly or wholly immersed in a fluid, it experiences an apparent loss in

• A. weight
• B. buoyant force
• C. liquid displaced
• D. none

Answer 1

The correct option is A weight

Weight.
Buoyant force is the upward force exerted by a fluid that opposes the weight of an immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus a column of fluid, or an object submerged in the fluid, experiences greater pressure at the bottom of the column than at the top. This difference in pressure results in a net force that tends to accelerate an object upwards.

The magnitude of that force is proportional to the difference in the pressure between the top and the bottom of the column, and (as explained by Archimedes principle) is also equivalent to the weight of the fluid that would otherwise occupy the column, i.e. the displaced fluid. For this reason, an object whose density is greater than that of the fluid in which it is submerged tends to sink. If the object is either less dense than the liquid or is shaped appropriately (as in a boat), the force can keep the object afloat.