Question

Explain why: (a) A pencil will write on paper but not on glass (b) The handles of motor cycle are covered with a rubber sheet with spikes (c) The soles of our shoes wear out gradually. (d) Tyres of car wear out gradually

Answer 1

a) A pencil will write on paper not on glass because paper provides more friction than glass. Writing is possible due to friction only.
b) The handles of a motor cycle are covered with rubber sheet with spikes to make the surface rough and to increase grip on the handle so that our hands don't slip.
c) We can walk due to friction. The soles of our shoes wear out due to friction between the soles and the surface.
d)Same as above. The tyres being constantly in contact with surface on which it is kept wears them down.