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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Davneet Singh
Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.