Question

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

Answer 1

Pressure:

1. Pressure is the force applied per unit area by one object on another.
2. The surface area on which the force operates is inversely proportional to the pressure. The smaller the surface area, larger is the pressure exerted.
3. Because the pressure on the shoulders is relatively large, it is difficult to handle a school bag with a thin strap.
4. The contact surface area of a narrow strap is extremely small. As a result, the shoulder is under a lot of stress.

Thus, it is difficult to hold a school bag having a strap made of a thin and strong string