Question

what is buoyant force? and in which direction it acts?

Answer 1

the force experienced by an object when it is placed in water in presence of air

Answer 2

The buoyant force is the force exerted by water when any object is immersed in it. When an object is immersed in liquid, two forces acts on it. The force due to gravitational attraction of Earth pulls it downward. The water applies and upward force. Thus, the object is pushed upwards. Buoyant force is also called upthrust. It always acts in upward direction, i.e., opposite to the gravitational force.
Buoyant force is the reason that everyone (or maybe only Indians including me) float when we go to take a bath in river. And that's the reason why in some films, the villain ties a big stone along the hero and then throws him in water. The stone has huge mass and buoyant force acting on it is very low to let the man go to top.

Buoyant force exerted by air is normally called air resistance.

Hope my answer helps you! :-)

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