Assertion (A): An iron ball floats on mercury but gets immersed in water. Reason (R): The specific gravity of iron is more than that of mercury.Codes:
✓ Correct answer: c) A is true but R is false
ExplanationDensity is a measure of how much mass is packed into a given volume.Buoyancy is the tendency of an object to float in a fluid.An object floats if its density is less than the fluid’s density and sinks if its density is greater.If the densities are equal, the object remains neutrally buoyant, neither sinking nor floating.Assertion (A) is true: Iron is denser than water, so it sinks in water.However, mercury is denser than iron, so an iron ball will float on mercury.Reason (R) is false: Specific gravity is the ratio of the density of a substance to the density of a reference substance (usually water).Mercury is denser than iron, so its specific gravity is higher.226
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