Define buoyant force. Mention its cause and give the factors affecting
buoyant force.
Answers
Answer:
Buoyancy or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid.
- The factors that affect buoyancy are… the density of the fluid. the volume of the fluid displaced. the local acceleration due to gravity.
- The buoyant force is not affected by… the mass of the immersed object. the density of the immersed object.
Buoyancy (/ˈbɔɪənsi, ˈbuːjənsi/)[1][2] or upthrust, is an upward force exerted by a fluid that opposes the weight of a partially or fully immersed object. In a column of fluid, pressure increases with depth as a result of the weight of the overlying fluid. Thus the pressure at the bottom of a column of fluid is greater than at the top of the column. Similarly, the pressure at the bottom of an object submerged in a fluid is greater than at the top of the object. The pressure difference results in a net upward force on the object. The magnitude of the force is proportional to the pressure difference, and (as explained by Archimedes' principle) is equivalent to the weight of the fluid that would otherwise occupy the submerged volume of the object, i.e. the displaced fluid.
For this reason, an object whose average density is greater than that of the fluid in which it is submerged tends to sink. If the object is less dense than the liquid, the force can keep the object afloat. This can occur only in a non-inertial reference frame, which either has a gravitational field or is accelerating due to a force other than gravity defining a "downward" direction.[3]
The center of buoyancy of an object is the centroid of the displaced volume of fluid.