# Inertia

Inertia . Property of a physical or social system that makes it oppose possible changes. In physics it is said that a system has more inertia when it is more difficult to achieve a change in its physical state.

.

## Summary

[ hide ]

• 1 Definition
• 2 Inertia as property of Matter
• 3 Examples of Inertia
• 4 Sources

## Definition

Property of a physical or social system that makes it oppose possible changes. In physics it is said that a system has more inertia when it is more difficult to achieve a change in its physical state. The two most frequent uses in physics are mechanical inertia and thermal inertia. The first of these appears in mechanics and is a measure of difficulty in changing the state of movement or rest of a body. Mechanical inertia depends on the amount of mass and the inertia tensor. Thermal inertia measures the difficulty with which a body changes its temperature when in contact with other bodies or being heated. Thermal inertia depends on the amount of mass and the heat capacity.

## Inertia as property of Matter

Inertia, property of matter that makes it resist any change in its movement, either in direction or speed . This property is accurately described in British scientist Isaac Newton’s first law of motion: an object at rest tends to remain at rest, and a moving object tends to continue to move in a straight line, unless a force acts on them. external.

Example of inertia

For example, passengers in an accelerating car feel the force of the seat against their backs, which overcomes their inertia and increases their speed. When it brakes, passengers tend to keep moving and are thrown forward. If you make a turn, a package placed on the seat will move laterally, because the inertia of the package makes it tend to keep moving in a straight line.

## Examples of Inertia

Any body that rotates around an axis exhibits inertia to rotation, that is, a resistance to change its speed of rotation and the direction of its axis of rotation. The inertia of an object to rotation is determined by its moment of inertia. Changing the rotational speed of an object with a high moment of inertia requires a greater force than if the object has a low moment of inertia. The flywheel located on the crankshaft of automobile engines has a high moment of inertia. The motor supplies power to blows; the high inertia of the steering wheel cushions those blows and makes the power transmit to the tires smoothly.

The inertia of an object to translation is determined by its mass. The second law of Newton states that the force acting on an object is equal to the mass of the object multiplied by the acceleration experienced. Therefore, if a force causes an object to undergo a certain acceleration , a greater force will have to be applied to make an object with greater mass undergo the same acceleration. For example, to be able to drag a shoe box or a package with several of these boxes on the same pavement, and with the same speed, it will be necessary to apply a greater force to the package, since it has more inertia. (See Speed).