Speed, Time and Distance Concepts and Formulas

Points to remember:

1.) Speed: The rate at which an object is moving is known as its speed. It is the distance traveled per unit time e.g. an object moving at 20 m/s shows that the object covers a distance of 20 meters every second.

The formula for speed: Speed =

Therefore, Time =

And, Distance = Speed x Time

2.) A man covers a certain distance D1 km at a speed of S1 km/hr and, D2 km at a speed of S2 km/hr, his average speed during the whole journey is given by:

Average speed =km/hr

3.) A man travels from P to Q at a speed of S1 km/hr and returns from Q to P at S2 km/hr, his average speed during the whole journey is given by:

Average speed =

4.) Two men A and B start travelling at the same time from points P and Q towards each other and after crossing each other A takes time T1 to reach Q and B takes time T2 to reach P,:

5.) If a man travels at of his usual or original speed, the change in time taken to cover the same distance is given by:

Change in time = * usual or original time

6.) A man covers a distance D in time T1 with speed S1. When he travels at speed S2 and covers the same distance D in time T2,;

You can equate any two of the above relations to find the unknown values.

7.) A body covers a certain distance at a speed of S1 km/hr without stoppage and with stoppage it covers the same distance at S2 km/hr, the stoppage time per hour is given by: