Simple centripetal acceleration question

AI Thread Summary
In circular motion, centripetal acceleration is always directed towards the center, and its magnitude is given by v^2/R. The sign of the acceleration does not affect its direction, as both positive and negative values indicate the same inward direction. The distinction between using -v^2/R and +v^2/R is primarily a matter of convention rather than a change in the physical meaning. Ultimately, the focus should be on the magnitude and direction of the acceleration rather than the sign. Understanding that velocity and acceleration are vectors is crucial in this context.
StephenD420
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Hello everyone

When do you use -v^2/R instead of positive v^2/R for the acceleration in circular motion?

Thanks.
Stephen
 
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Remember that velocity and acceleration are vectors.
 
so whenever the velocity is pointing to the left?
 
Centripetal acceleration keeps changing its direction, so I don't think the sign has any significance there.
 
StephenD420 said:
When do you use -v^2/R instead of positive v^2/R for the acceleration in circular motion?
v^2/R gives you the magnitude of the acceleration; the direction is always towards the center.
 
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