Let's do something related to physics.

                                   Hi guys, this time it's a physics lesson. 

Have you observed the objects around you? Some of them are stationary and some moves. Let's talk about the motions of those moving objects. 

An electric fan is an example for rotation.

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The planets around the sun are examples for Revolution.

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Pendulum of a clock is an example for Oscillation.

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A runner running 100m race is an example for Linear motion.

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Let's talk about Linear motion.

A straight motion of a moving object can be referred to as a Linear motion. 

What is distance?

The length moved by a moving object can be defined as Distance in short terms. 

What is Displacement?

The shortest distance between two places is Displacement in short terms.

Scalar quantity and Vector quantity

Quantities with magnitude but no direction is a Scalar quantity.

Quantities with both magnitude and direction is a Vector quantity.

So distance is a Scalar quantity while displacement is a vector quantity.

Check the diagram below.

Here the vehicle travels from point A to point B. 

He travels from point A to C, D and finally to B.

Distance = 6+4+6+3

                 = 19 km

Displacement = 4+3

                           = 7km/South

When stating displacement, we must state the direction of the place from which it moved.

For further clarification, let's find the displacement here.

The vehicle moves on the same path first 6km east and then back 9km west.

So the displacement is 3km/West.

Speed

The rate of change of distance is known as Speed.

The SI unit of speed is meters per second(m s-1)

Velocity

The rate of change of displacement is known as Velocity.

The SI unit of velocity is meters per second(m s-1)

Are the velocities same?

The answer is No. Because the direction varies. 

Hope you learnt something

Thank you for stopping by