Types of motion

Types of motion

In our day‒to‒day life the following kinds of motion are observed:

a. Linear motion

An object is said to be in linear motion if it moves in a straight line.

Examples

·           An athlete running on a straight track

·           A particle falling vertically downwards to the Earth.

b. Circular motion

Circular motion is defined as a motion described by an object traversing a circular path.

Examples

·           The whirling motion of a stone attached to a string

·           The motion of a satellite around the Earth

These two circular motions are shown in Figure 2.5

c. Rotational motion

If any object moves in a rotational motion about an axis, the motion is called ‘rotation’. During rotation every point in the object transverses a circular path about an axis, (except the points located on the axis).

Examples

·           Rotation of a disc about an axis through its center

·           Spinning of the Earth about its own axis.

These two rotational motions are shown in Figure 2.6.

d. Vibratory motion

If an object or particle executes a to-and- fro motion about a fixed point, it is said to be in vibratory motion. This is sometimes also called oscillatory motion.

Examples

·           Vibration of a string on a guitar

·           Movement of a swing

These motions are shown in Figure 2.7

Other types of motion like elliptical motion and helical motion are also possible