### Theory:

In this exercise, We will learn about speed and its various types.

Speed simply tells us how fast an object can move.

Speed is a scalar quantity, which only tells the magnitude (numerical value) of how much speed that an object travels.

Speed:
Speed is the rate of change of distance.

$\mathit{Speed}=\frac{\mathit{Distance}\phantom{\rule{0.147em}{0ex}}\left(d\right)}{\mathit{Time}\phantom{\rule{0.147em}{0ex}}\left(t\right)}$
The SI unit of speed is $\frac{\mathit{meter}\phantom{\rule{0.147em}{0ex}}\left(m\right)}{\mathit{second}\phantom{\rule{0.147em}{0ex}}\left(s\right)}=\frac{m}{s}=m{s}^{-1}$

And, if we want to calculate the distance using speed and time, we can use the following formula,

$\mathit{Distance}\phantom{\rule{0.147em}{0ex}}=\mathit{Speed}×\mathit{Time}$.
We can classify the speed into two types with respect to distance and time.

Two types of speed:
• Uniform speed
• Non-uniform speed
Uniform speed:
If an object in motion covers equal distances in equal intervals of time, then the object is said to be at a uniform speed.
Example:
In our daily, life we can see the uniform motion in the following situation:

1. The circulation of blood in our body.

2. Movement of hands in a watch.

3. The movement of the fan and mixer in our kitchen at a particular speed.

4. The Earth and Moon rotate almost at a uniform speed.
Non-uniform speed:
If an object covers unequal distances in equal intervals of time, the object is said to be in non-uniform speed.
Example:
1. A car coming to a halt.

2. The object will moves at non-uniform speed, if it is thrown into the air, -for example, a cricket ball or stone.

3. The moment of a vehicle in traffic.
Average speed:
We can calculate the average speed of an object by dividing the total distance travelled by the object and the total time taken to travel the distance.

That is,