Force: Interaction Of Forces And Change In Shape Due To Force

What is Force and how does interaction of forces work?

Before we dwell into how force can affect the state of motion of a body, let’s take a glance at force. Force is an interaction between two or more bodies that when unopposed causes a change in the state of motion of the objects. So in the definition of force itself, it explicitly states that force is something that causes a change in the state of motion. Interaction of forces can also be thought of as a push or a pull. A change in the state of motion corresponds to either a change in the speed of the body and/ or a change in the direction of motion of the body. The change in speed could mean a speeding up (acceleration) or speeding down (deceleration). A ball cannot move on its own, neither can a chair or a table. All non-living objects are stationary unless a force is acting on them. You need to have an engine to generate force in order to make it move, you need to kick the ball which is a form of applied force in order for the ball to fly into the goal. Sometimes multiple forces can act on the same body. Imagine that you are kicking a ball and your friend has the exact same idea. What would happen if you both kicked the ball simultaneously? Let’s find out.

Interaction of Forces

Force that changes shape

Interaction of Forces

Have you played the tug-of-war with your friends? What happens in a tug-of-war is that two teams pull a single rope. The team that is able to pull the rope by a certain amount in spite of the other team pulling it wins. So what exactly is going on here? In a tug-of-war game, two forces are acting in opposite directions. One team is pulling the rope towards the right and another is trying to pull the rope to the left just as hard. This causes both forces to cancel each other out in much the same way as -3 and +3 cancel each other out. That’s one scenario taken care of. What happens if forces are acting in the same direction? Is it easier to push a car by yourself or with the help of a couple of your friends? It is easier if you push the car together right? This is because force adds up too. When you and your friends are pushing in the same direction, all your forces combined are acting on the car hence making it easier to push it together. To summarize, if forces are acting in opposite directions they cancel each other out and if they are acting in the same direction, they add up.

The Effect of Force on the Shape of an Object

Have you ever played with clay? It is an extremely unusual material. When you press a ball of clay, it doesn’t move. It loses its shape instead. You must have seen your mother mixing the dough to make chapattis. Have you felt the dough? When you press the dough, it changes its shape with the force applied. It does it so well in fact if you notice closely, even you fingerprints are pressed into the dough. This is a property of the material. This is in contrast to some other materials such as rubber bands and springs. Materials such as those change their shape on the application of force but when the force is removed the material returns back to its original position. The materials which change their shapes permanently on the application of force such as clay and dough are called Plastic materials. This is not to be confused with actual plastic. Materials that undergo shape change on the application of force but regain their original shape on the removal of force are called Elastic materials.

To summarize, in this article, we discussed the interaction of forces and the change in the shape of the object on the application of force. To find more such article, please visit BYJUs.com for more information. Join us and fall in love with learning.


Practise This Question

Which of the following statements are correct for a round trip along the same route?