What is relative velocity
Asked by dibyanshubehera2727 | 2nd Jul, 2021, 07:28: AM
When an object is moving in a medium, if medium also under motion , then the motion of medium
observed from the moving object is called relative motion.
Velocity of moving medium observed from the object is relative velocity.
This is because velocity observed by an observer who is at rest is differenct from the velocity observed by an observer in the moving object.
Let us consider the example of boat moving in a river.
Let u be the velocity of river and v be the velocity of boat.
In the upstream direction, i.e., when boat moving in the direction opposite to the direction of motion of river ,
velocity of river observed by observer in the boat is ( u+v )
In the downstream direction. i.e., when boat moving in same direction as the direction of motion of river ,
velocity of river observed by observer in the boat is ( u - v )
Answered by Thiyagarajan K | 2nd Jul, 2021, 09:04: AM
- According to relative velocity formula we know that when two bodies move towards each other the relative velocity is equal to the sum of two velocities. Then why in calculating upstream where the direction of velocity of stream is against the direction of velocity of boat in still water we subtract the former from the latter even when they are opposite to each other?
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