sign convention in ray optics
Asked by mkiruthiga90 | 14th Dec, 2018, 07:32: PM
Expert Answer:
There are two types of sign convention used in ray optics
1. Cartesian sign cones
2. Real sign convention
You can use any one of them but for CBSE board exams always use cartesian sign convention.
In cartesian sign convention direction of incident ray is taken as +ve . If incident is travelling from left to right the distance, measured along right direction will be taken as positive. We can treate this direction as +ve x axis direction and rest can be decided on the basis of graph that we use in mathematics. Like upward direction will be taken as +ve as its is +ve y axis. And downward as -ve .

Answered by Ankit K | 14th Dec, 2018, 10:52: PM
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