Why does an object float or sink when placed on the surface of water?

Answer

If the density of an object is more than the density of the water, then it sinks.

This is because the buoyant force acting on the surface is less than the gravitational force acting on the surface.

If the density of an object is less than the density of the water, then it floats.

This is because the buoyant force acting on the surface is more than the gravitational force acting on the surface.

  1. Class 9
  2. Chapter 10 Class 9 - Gravitation

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CA Maninder Singh
CA Maninder Singh is a Chartered Accountant for the past 9 years and a teacher from the past 16 years. He teaches Spoken English, Written English, Grammar and Vocabulary at Englishtan.