Birds such as ducks, geese, and swans have greater densities than water, yet they are able to sit on its surface. Explain this ability, noting that water does not wet their feathers and that they cannot sit on soapy water.
We know that buoyancy force is the force responsible for an object to float over a liquid and it depends on the density of the liquid and the object. That is the object’s density should be less compared to the liquid density to float over the water.
In the case of birds such as ducks,geese and swans have greater densities than water even though they can sit on the water surface, the reason for this isThese bird’s feathers are created in such a way that it won’t get wet because they possess a particular gland called the preen gland, which produce a water repellent oil which is supplied over its feathers.These bird’s have hollow bones which have a very less weight.The lungs of these birds plays a role to make them float on water, the lungs contain air sacs which help them to carry air in order to float over the water.