Question 1 What makes the steps of foot over bridges at railway station to wear out slowly? Question 2 Which part wear away first in shoe?Give a reason for your answer? Question 3 Why do brake pads of bicycles have to be replaced quite often? Question 4 A pencil eraser loses tiny pieces of rubber each time you use it.Why does this happen? Question 5 What happen when … [Read more...] about Disadvantages of friction