JEE Mains · Physics · STD 12 - Ray optics and optical instruments
- JEE Mains 2021
- Hard
- MCQ
The incident ray, reflected ray and the outward drawn normal are denoted by the unit vectors \(\overrightarrow{ a }, \overrightarrow{ b }\) and \(\overrightarrow{ c }\) respectively. Then choose the correct relation for these vectors.
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(\overrightarrow{ b }=\overrightarrow{ a }-2(\overrightarrow{ a } \cdot \overrightarrow{ c }) \overrightarrow{ c }\)
Step-by-step Solution
Detailed explanation
\(\overrightarrow{ a }=\sin \theta \hat{ i }-\cos \hat{ j }\)
\(\overrightarrow{ b }=\sin \theta \hat{ i }+\cos \theta \hat{ j }\)
\(\overrightarrow{ c }=\hat{ j }\)
\(\overrightarrow{ a }-2(\overrightarrow{ a } \cdot \overrightarrow{ c }) \overrightarrow{ c }=\sin \theta \hat{ i }+\cos \theta \hat{ j }\)
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