Question

Which of the following floats on water?
(A) Air filled tube of a tyre
(B) A sharpener
(C) A stone
(D) A chain

Answer 1

Hint: We are looking for the material that would float on water. It requires a concept of density. The density of the substance that floats on water has to be less than that of water.

Complete step by step answer
It is already known that anything which is less dense than water will float on water.
So, the density of the material should be less than water.
Here, in case of stone, chain, sharpener are solid materials which are made of materials which are dense enough to draw in water.
Air filled tube floats on water as it contains air and which is very less dense than water. So, we need to see from the above options, and select the correct value.
Thus, the correct answer is option A.

Additional Information
Paper floats because it is less dense than water, so it floats to the surface. However, if it gets completely soaked then it will become denser than water and sink. When objects sink, the volume of water they displace is greater than the volume of the object. The principle may seem relatively simple: Light objects float and heavy objects sink. However, we can make even heavy objects float by taking advantage of surface area and weight dispersal.

Note
Some examples of materials that will float in water are objects like apples, wood, and sponges are less dense than water. They will float. Many hollow things like empty bottles, balls, and balloons will also float. That's because air is less dense than water. These objects float on water because these objects have tightly packed molecules that are denser than those where the molecules are spread out. Density plays a part in why some things float and some sink. Objects that are denser than water sink and those less dense than water floats. Lighter liquids (like water or vegetable oil) are less dense than heavier liquids (like honey or corn syrup) so they float on top of the heavier liquids.