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MODEL PAPER 5 — Physics STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 SciencePhysicsMODEL PAPER 51 Mark
Question
Assertion (A): According to Huygen’s principle, no backward wave-front is possible.
Reason (R): Amplitude of secondary wavelet is proportional to $(1+\cos \theta)$ where $\theta$ is the angle between the ray at the point of consideration and the direction of secondary wavelet.
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Answer

(b) Both A and R are true but R is not the correct explanation of A.
Explanation: Both A and R are true but R is not the correct explanation of A.

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