Chapter 1 (Motion)

Motion:

If anybody changing its position with respect to time, then the body is said to be in

motion.

Or

A body is said to be in motion if it changes its position continuously with respect

to a stationary object taken as a reference point.

For example:

Let us consider two points A and B is far apart with each other, an object starts

changing its position from A to B with time then the object is said to be motion.

 

Distance:

The total length of the path travels by a body.

Example:

In the given image, Both of the figures represent the length of the path from A to B.

And both are the Distance. It is denoted by “s“, and it’s SI unit is m.

Displacement:

The minimum distance between the starting point and the ending point is known as

Displacement. It is also denoted by “s“, and it’s SI unit is m.

 

Example:

In the above image, the first figure represents the Displacement. And the second

one represents the Distance.

One more Image related to Distance and Displacement.

 

Difference Between Distance And Displacement:

Distance:

Total length between starting and the ending point.

It is a scalar quantity (it has only magnitude).

It can’t be zero and negative.

Displacement:

The minimum length between starting and the ending point.

It is a vector quantity (it has both direction and magnitude).

It can be positive, negative, and as well as zero.

Uniform Motion:

If anybody travels the equal distance in an equal interval of time, then its motion is

said to be a uniform motion.

For Example:

Non-Uniform Motion:

If anybody travels the unequal distance in an unequal interval of time, then it’s

motion is known as Non-Uniform Motion.

For Example:

In the given figure, a car travels the irregular distance in the unequal interval of time.

Speed:

The rate of change of distance w.r.t (with respect to) time is known as speed. Speed

is denoted by “v“. Its SI unit is m/s.

The formula for the calculation of Speed(u) is given below ;

u=s/t

Average Speed:

It is defined as the total distance traveled by a body divided by the total time taken.

Its unit is m/s, and it is also represented by “v“.

The formula for the calculation of Average Speed(u)

Average Speed(u) = Total distance / Total time taken

Uniform Speed(or constant speed):

If anybody travels the equal distance in equal interval of time, its speed is known as

Uniform Speed.

Velocity:

The rate of change of displacement w.r.t to time is called displacement. It is denoted

by “v“, and it’s SI unit is m/s.

The formula for the calculation of Velocity(v) is given below;

Velocity(v)=Displacement(s) / Time Taken(t)

Initial Velocity:

When the observer starts his observation, then the velocity is known as

Initial Velocity. It is denoted by “u”.

Final Velocity:

When the observer ends his observation, the velocity is known as Final Velocity.

It is denoted by “v”.

Note:- m/s is the SI unit of both initial and final velocity.

Difference between Speed and Velocity:

Speed

It depends upon, distance and time.

It is a scalar quantity.

It can’t be negative and zero.

Velocity

It depends upon, displacement and time.

It is a vector quantity.

It can be positive, negative, and as well as zero.