Question

Question 1
Why is it difficult to hold a school bag having a strap made of a thin and strong string?

Answer 1

We know that pressure exerted by a force is inversely proportional to the surface area on which it acts. Smaller the surface area; larger will be the pressure. In case of a thin strap, the contact surface area is small. Hence, the pressure exerted on the shoulder is large. This explains why it is difficult to hold a school bag having a thin strap.