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CBSE Class 12-science Answered

Sign convention in concave mirror
Asked by raushankumarmushkipur | 02 Apr, 2021, 10:08: AM
answered-by-expert Expert Answer
New Cartesian Sign Convention is followed to deal with the reflection of light by spherical mirrors.
 
In this convention, the pole (P) of the mirror is taken as the origin. The principal axis of the mirror is taken as the x-axis (X’X) of the
coordinate system. The conventions are explained as follows with the help of figure given above
 
 
(i) The object is always placed to the left of the mirror. This implies that the light from the object falls on the mirror
from the left-handside.

(ii) All distances parallel to the principal axis are measured from the pole of the mirror.
 
(iii) All the distances measured to the right of the origin (along + x-axis) are taken as positive while those measured to the left of
the origin (along – x-axis) are taken as negative.
 
(iv) Distances measured perpendicular to and above the principal axis (along + y-axis) are taken as positive.
 
 
(v) Distances measured perpendicular to and below the principal axis (along –y-axis) are taken as negative.
Answered by Thiyagarajan K | 02 Apr, 2021, 10:33: AM

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CBSE 12-science - Physics
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