Question

perform a friction test using an inclined plane, a pencil cell, a sand paper, a towel and various other surfaces.
1. why does the time taken by the pencil cell differ on the different surfaces?
2. what do we conclude from this activity?
please help, i need it urgently!

Answer 1

Ans.1. We know that friction is the opposing force which results from the adhesion&cohesion property between the materials at the molecular level. We also know that friction also depend upon the nature of the surfaces of the materials on which it is applied. Hence, when we use different types of surfaces, obviously there will be various 'time taken' as well.

Ans.2. Ultimately, we can conclude or we can say that it is a type of proof that friction also depend upon the nature of the surfaces of the objects.  

Answer 2

If I move pencil cell on inclined plane it moves very easier but it is harder to move on sand paper and very difficult to move on towel because friction is less on inclined plane as it is smother and doesn't have much groves and ridges to stop and move the object and on the sand paper we can see rough surface having more groves and ridges which are short performs friction more than plane and towel it too difficult to move cell as if friction is more and more asit has large and many groves and ridges which can stop the cell easily so, we can conclude that friction is different in each case and indirectly leads other objects