Thu January 03, 2013 By: Satyarth Agrahari

distance cannot be negative, but according to new cartesian system the distance of object(since kept on left) is taken negative.why is it so?

Expert Reply
Fri January 04, 2013
The negative sign is taken just to signify that the distance to the object is measured in the direction opposite to that of light.
For eg., consider a number line. Lets assume that the mirror is placed at such a position that its pole lies at the zero point of the number line, object is placed on the negative side and light enters the lens from the negative side. Then in such a case the distance to the object (measurd from pole) is taken as negative.
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