Question

What do you meant by force of friction? Also prove force depends on nature of two surface in contact

Answer 1

Force is a push or pull on an object is called a force.Friction means when we apply force on any object than that object will said to be in motion.We can say that the friction stop the the object that is in motion.No it is not of nature as it depend on us to apply force. Yes force is depend on two surfaces.

Answer 2

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Friction is the force that opposes motion between any surfaces that are in contact.

Let us put a pencil on a polythene sheet and release it without any push and note down the distance covered by pencil on polythene sheet.After this put the pencil on a thin layer of land and note the distance covered by pencil.We observed that the pencil covers minimum distance on a polythene sheet because distance covered by pencil depends upon the nature of surfaces.It covers lower distance when surface is rough because rough surfaces provide more friction than the smooth surfaces.