DISTANCE, DISPLACEMENT, SPEED AND VELOCITY

Distance, Displacement, Speed and Velocity.

Distance and Displacement.

Distance : Total length of distance travelled. Distance is called as scalar quantity since it has magnitude and no direction. To better differentiate distance from displacement is that distance is the long way from the initial point to the final point.

Displacement : The total distance travelled in a specific direction. Displacement is a vector quantity since it has magnitude and direction. Displacement a.k.a. shortcut is the path with the shortest length that links the initial point to the final point.

Still confused ? Here's a simple example.

Distance : I tell you to walk 5m, then 3m. Where are you ?

Displacement : I tell you to walk 5m backwards, then 3m to the left. Where are you now ?

Obviously, in both situations, you are in different places and this is due to the direction you took. In distance, you had the freedom to choose which ever direction you want but in displacement, you followed the given directions. But when in comes to calculations, distance is the total length of the whole diagram while displacement is the length/shortcut between the initial point and the final point. Faham ?

Speed and Velocity.

Speed : The rate of change of distance. A scalar quantity since it has no direction.

Speed, v = Total distance travelled, s (m)

             Time taken, t (s)           

Velocity : The rate of change of displacement. A vector quantity since it has both magnitude and direction.

Velocity, v = Displacement, s (m)

                   Time taken, t (s)  

Alright, that is all for now. The next post will be about average speed and average velocity, acceleration and deceleration. Do comment for any wrong facts or if you simply do not understand.