Please tell me the sign convension for velocity & accleration for a body moving upwards ,downwards, right and left relative to another body? (Apoorv Katoch asked)
Answer: In motion, sign conventions are arbitrary. You take one direction as positive and the direction opposite to it as negative.
For example, if you consider a body projected vertically upwards, and if you take the initial velocity as positive, then all measurements taken in the upward direction will be taken positive and all measurements taken in the downward direction is taken negative.
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