WHAT IS FORCE?
In Class VII, you have learned how objects move. Do you recall how we can decide whether an object is moving faster than the other? What does the distance move by an object in unit time indicate? You also know that a moving object like a ball rolling on the ground goes slower. Sometimes it may change its direction of motion. It is also possible that the ball may go slower and also change its direction. Have you ever wondered what makes an object move slower or go faster, or change its direction of motion?
Let us recall some of our everyday experiences. What do you do to make a football move? What do you do to make a moving ball move faster? How does a goalkeeper stop a ball? A hockey player changes the direction of the moving ball with a flick of the stick. How do fielders stop a ball hit by a batsman? (Fig. 11.1). In all these situations the ball is either made to move faster or slower or its direction of motion is changed.
Figure 11.1(a): A goalkeeper saving a goal,
Figure 11.1(a): A hockey player flicking a ball, and
Figure 11.1(a): A fielder stopping a ball
We often say that a force has been applied on a ball when it is kicked, pushed, thrown, or flicked.
What is a force? What can it do to the bodies on which it is applied? We shall seek answers to such questions in this chapter.
Source: This topic is taken from NCERT TEXTBOOK