ALWAYS WRITE THE DIRECTION OF THE V

ALWAYS WRITE THE DIRECTION OF THE VELOCITY OF AN OBJECT.
You have learnt so far that an object that changes its position with time has a non-zero velocity. When we talk about the change in position of an object, we have to include the direction of motion. If the velocity of an object is to be increased, its change in position from the initial position, that is, its displacement should be increased with time. This object should never change direction and return to where it started from!
Now think of this situation: Suppose you are travelling in a train. Do you always move at the same speed or with the same velocity? The train stops at different stations. Sometimes it moves fast and at other times it slows down. So its speed and velocity change at every instant of time. The average velocity does not tell us how fast an object moves at any given instant. To describe this kind of motion, we use words like instantaneous velocity and instantaneous speed.
INSTANTANEOUS VELOCITY AND SPEED
INSTANTANEOUS VELOCITY IS VELOCITY AT EACH INSTANT OF TIME.
INSTANTANEOUS SPEED IS SPEED AT EACH INSTANT OF TIME.