Weather an object will float or sink in a liquid, depends on

CONCEPT

• Density: It is defined as the mass of a body per unit volume. We can also say that how much mass it can contain in a specific volume.

• As of dense material like Iron takes more mass in a given volume than of wood.
• Mathematically it gives a formula Density (ρ) = mass (m) / Volume (V)
• SI Unit is kg/m³.
• 1m³ = 1000 litres of water.

• Flotation: It can be defined as the tendency of an object to rise to the upper levels of the fluid or to stay on the surface of the fluid.
• Sinking: The opposite of floatation is sinking and can be defined as the tendency of an object to go to the lower levels of the fluid.

EXPLANATION

• Flotation and sinking of an object is dependent upon the relative density with each other.

• If the density of the object is more than the density of the liquid, the object will sink.
• On the other side, if the density of an object is less than the liquid, then it will float over it.
• If the density of object and liquid is equal to each other, they are in equilibrium and float and sink both at the same time

Therefore, the sinking or floating of an object depends on the difference of density of object and liquid.

⇒ Option 3 is correct