We have already learned about motion and its different types based on how the objects are moving.

We also studied that when objects are in motion, their speed is calculated as $speed=timedistancecovered $ .

The relation between speed, distance and time is shown above.

Depending on speed and how it varies, motion is of two types - Uniform motion and Non-uniform motion.

In this story let us focus on Uniform Motion

An object is said to be in uniform motion, when it's speed and direction remains same throughout the motion.

Suppose we are moving through a highway which has a speed limit of 40 km/hr.

We still have to go 120 km to reach our destination in minimum time possible.

Then how much time do we have in our hand ?

As this highway has a speed limit, we cannot increase our speed beyond 40 km/hr and at the same time, cannot decrease it too, otherwise we will reach late.

With this constant speed how much distance are we covering in our 1st hour ?? $Distance=Speed$ x $time$= 40 km/hr x 1 hr = 40 km.

What about the distance covered in 2nd hour - Distance = 40km/hr x 1 hr = 40 km.

And in the 3rd hour also the distance covered is 40 km.

Since our speed remained constant throughout the journey, we covered equal distances (40km) in equal intervals of time (1 hr).

Our speed remained constant and also our direction did not change. So, we are in - $UniformMotion$ .

So uniform motion also means - "equal distances in equal intervals of time" .

What about the motion of hands in a clock ?? Are they in Uniform Motion too ??

The hands always covers equal distance (one circle) in equal intervals of time (for every minute or hour). So, of course its in Uniform Motion, isn't it ?

Wait ! Only constant speed doesn't mean that the object is in uniform motion... We should also check its direction !

An object will be in uniform motion only when both it's speed and direction are not changing.

In the case of hands of a clock, although the speed remains constant, the direction of the hands is always changing.

Thus, they are NOT in Uniform Motion.

Similarly, revolution of earth around sun is also not uniform motion.

Although earth makes one revolution (same distance) in every year (equal intervals of time), its direction continuously changes,

So, the motion of all such objects moving in a circle with constant speed will NOT be an Uniform Motion. This we will learn in more detail while studying $UniformCircularMotion$ .

For now, let's revise what we discussed about Uniform Motion

When objects are in uniform motion, their speed and direction remains constant.

Objects in uniform motion covers equal distances in equal intervals of time.