Force OF Buoyancy

Let T represent the true weight of a body, B the force of buoyancy on the body when immersed in a liquid. A represents the apparent weight of the body and W be twice the weight of liquid displaced by te body. Then which of the following relation is correct?

The force of buoyancy exerted by the atmosphere on a balloon is B in the upward direction and remains constant. The force of air resistance on the balloon acts opposite to the direction of velocity and is proportional to it. The balloon carries a mass M and is found to fall down near the earth's surface with a constant velocity v. How uch mass hsould be removed from teh balloon so that it may rise with a constant velocity v?

Centre Of Buoyancy

It is found that the measured weight ( ne zero) of an empty thin polythene bag has not changed when the bag in filled with air. Two students were asked reason for this : Saara: Air is so light that weighing machine need to have large precision to measure weight of filled air. Vasu : Force of buoyance increases by the same amount as the weight of added air .

If a body moves through a liquid or a gas then the fluid applies a force on the body which is called drag force. Direction of the drag force is always opposite to the motion of the body relative to the fluid. At low speeds of the body, drag frog ( F _(P)) is directly proportional to the speed. F_(D) = kv What K is a proportionally constant and it depends upon the dimension of the body moving in air at relatively high speeds, the drag force applied by air an the body is proportional to v^(2) Where this proportionally constant K can be given by K_(2) rho CA Where rho is the density of air C is another constant givig the drag property of air A is area of cross-section of the body Consider a case an object of mass m is released from a height h and it falls under gravity. As it's speed increases the drag force starts increasing on the object. Due to this at some instant, the object attains equilibrium. The speed attained by the body at this instant is called "terminal speed" of the body. Assume that the drag force applied by air on the body follows the relation F_(D) = kv ,neglect the force by buoyancy applied by air on the body then answer the following questions. What is the pattern of acceleration change of the body ?

If a body moves through a liquid or a gas then the fluid applies a force on the body which is called drag force. Direction of the drag force is always opposite to the motion of the body relative to the fluid. At low speeds of the body, drag frog ( F _(P)) is directly proportional to the speed. F_(D) = kv What K is a proportionally constant and it depends upon the dimension of the body moving in air at relatively high speeds, the drag force applied by air an the body is proportional to v^(2) Where this proportionally constant K can be given by K_(2) rho CA Where rho is the density of air C is another constant givig the drag property of air A is area of cross-section of the body Consider a case an object of mass m is released from a height h and it falls under gravity. As it's speed increases the drag force starts increasing on the object. Due to this at some instant, the object attains equilibrium. The speed attained by the body at this instant is called "terminal speed" of the body. Assume that the drag force applied by air on the body follows the relation F_(D) = kv ,neglect the force by buoyancy applied by air on the body then answer the following questions. What is the terminal speed of the object ?

Pressure In Fluids (Static Condition )|Pascal's Law|Some Applications Of Pascal's Law|Concept Of Buoyancy|Why Objects Float And Sink In Water|Floating| Important Points|Summary

Pascal's Law | Pressure Variation in Liquid in Accelerating Container | Rotating Container | Buoyant force | Archimedes Principle | Floatation | Centre of Buoyancy

A raindrop with radius R = 0.2 mm falls from a cloud at a height h = 2000 m above the ground. Assume that the drop is spherical throughout its fall and the force of buoyance may be neglected, then the terminal speed attained by the raindrop is : [Density of water f_(w)=1000" kg m"^(-3) and Density of air f_(a)=1.2" kg m"^(-3),h=10" m/s"^(2) Coefficient of viscosity of air =1.8xx10^(-5)" Nsm"^(-2) ]

Bimettalic strip | Area expansion | Volume expansion: overflow problems | Buoyancy problems