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Assertion : Any ray of light suffers a d...

Assertion : Any ray of light suffers a deviation of `(180^@-2i)` after one reflection.
Reason : For normal incidence of light deviation is zero.

A

(a) If both Assertion and Reason are true and the Reason is correct explanation of the Assertion.

B

(b) If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

C

(c) If Assertion is true, but the Reason is false.

D

(d) If Assertion is false but the Reason is true.

Text Solution

AI Generated Solution

The correct Answer is:
To solve the question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that any ray of light suffers a deviation of \( (180^\circ - 2i) \) after one reflection. - When a ray of light strikes a reflective surface, it reflects off at an angle equal to the angle of incidence (according to the law of reflection: angle of incidence \( i \) = angle of reflection \( r \)). - The total deviation \( D \) can be calculated as the difference between the initial direction of the ray and its final direction after reflection. 2. **Calculating Deviation**: - The initial direction of the ray can be considered as a straight line (0 degrees). - After reflection, the ray deviates by an angle \( 2i \) (since it goes from \( i \) to \( r \)). - Therefore, the total deviation \( D \) is given by: \[ D = 180^\circ - 2i \] - This confirms that the assertion is true. 3. **Understanding the Reason**: The reason states that for normal incidence of light, the deviation is zero. - Normal incidence occurs when the angle of incidence \( i = 0^\circ \). - Substituting \( i = 0^\circ \) into the deviation formula: \[ D = 180^\circ - 2(0^\circ) = 180^\circ \] - This indicates that the deviation is not zero; instead, it is \( 180^\circ \). Thus, the reason is false. 4. **Conclusion**: - The assertion is true, while the reason is false. Therefore, the correct conclusion is that the assertion is correct, but the reason provided does not support it. ### Final Answer: - Assertion: True - Reason: False
To solve the question, we need to analyze both the assertion and the reason provided. ### Step-by-Step Solution: 1. **Understanding the Assertion**: The assertion states that any ray of light suffers a deviation of \( (180^\circ - 2i) \) after one reflection. - When a ray of light strikes a reflective surface, it reflects off at an angle equal to the angle of incidence (according to the law of reflection: angle of incidence \( i \) = angle of reflection \( r \)). - The total deviation \( D \) can be calculated as the difference between the initial direction of the ray and its final direction after reflection. ...
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