Types of Forces

Types of Forces

We have generally defined force as an external agency that changes the velocity of an object with a specified mass. Let us see in what situations the velocity or the state of objects are changed and thereby classify the types of forces:

• Contact Force
• Non Contact Force
• Tensile Force
• Normal Force

1) Contact Force
When a body is moving along the surface of another body, the motion is resisted by a force called frictional force. The frictional force is generated along the contact surface of both the bodies. The magnitude of a frictional force depends upon the nature of the materials of the bodies that are in contact. The next example, which is also encountered by us in real life is the frictional force.

2) Non Contact Force
The force which exists between two bodies which are not in contact with each other is a Non Contact Force. A very obvious force we see in day to day life is the gravitational force. Any object away from the earth is pulled towards earth by the force called gravitational force. Even if an object is moving upwards, the gravitational force tends to slow down the vertical movement of the object. The specialty of gravitational force is that it is a Non contact Force.

3) Tensile Force
We already explained that weight of an object is nothing but a type of gravitational force. When an object is suspended with a string, wire or a chain, the force of the weight of the body acting down is countered by an upward force as per Newton’s third law. This force is transmitted to the item used for suspension. Such a force is called Tensile Force. The material of the string, wire or chain should have the capacity to absorb this force, else it will get snapped.