Answer:
Bouyancy
Explanation:
Bouyancy occurs when the upthrust exerted on an object is equal to the weight of object displaced. It is mostly applicable to low density objects for example balloon. When balloon is displaced in water, it floats. This is due to the effect of the upthrust acting on the balloon which allows the balloon to float and which is opposite the weight.
Note that the weight acts downwards the object while the upthrust always acts opposite (upward)
