User: What is buoyant force?
Assistant: The upward force exerted on a body, partially or fully immersed in a fluid, is known as buoyant force. This upward force is also called Upthrust. This is related  to the Archimedes principle. If an object is partially or fully submerged in any fluid, the upward force and the fluid displaced is equal to the upward force exerted by the fluid.