Types of Inertia

There are three types of Inertia namely:

1. Inertia of Rest: The incapacity of an object or body to change its state of rest on its own is known as the inertia of rest. For example, when a car is suddenly started, the passengers in it fall backward
2. Inertia of Motion: The incapacity of an object or body to change its state of motion on its own is known as the inertia of motion. For example, in a moving car, when it suddenly stops, all the passengers fall forward.
3. Inertia of Direction: The incapacity of any physical object to change its direction of motion on its own is known as the inertia of direction. For example, when a car moves along a round curve, the passengers sitting inside are thrown outwards.

Let’s perform an activity to learn more about inertia as,

• Place a thick square card on the mouth of a glass tumbler, as shown in the illustration. A coin is then placed in the middle of this card. 

• At first, the card and the coin are in a condition of rest. When we strike the card with our fingers, a force operates on it, causing it to move from its resting state to one of motion. 
• As a result, the card travels away from the glass tumbler’s mouth. The force of our flick, on the other hand, has no effect on the coin, thus it remains in a condition of rest due to inertia. 
• Because of inertia, the penny falls into the glass tumbler when the card on which it had been placed moves away.

Many events are seen in the field of physics, yet some of them have eluded explanation for a long time. Newton proposed three rules of motion, which became known as Newton’s Laws of Motion. These laws were a novel finding in the physical universe, and they were frequently employed to explain situations that were before unexplainable. Newton’s three laws were utilized to establish a relationship between the motion of objects around us and the natural or external forces operating on them, as we all know. 

A push or pull on an object that causes the body on which it works to accelerate is known as Force. The Newton (N) is the SI unit of force. A force can affect a body in three ways. It has the ability to change the speed of a body, the direction of motion of a body, and the shape of a body. Force is a vector quantity since it has both magnitude and direction. Also, force exists only as a result of a collision. 

The force is no longer felt by the objects if there is no interaction. Similarly, inertia was utilized in conjunction with the first law of motion to describe physical phenomena. Before we look at what inertia is, it’s a good idea to review Newton’s first law: