1ans: θ=30°
2 mirrors are inclined at an angle θ as shown in figure.Light ray is incident parallel to one mirror.The ray will start retracing its path after the third collision if:
a)θ=45° b)θ=30° c)θ=60° d)all three
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7 Answers
1this question is from arihant,ans given is 30° strangely..
i proceeded like souradeep and surely 45° gives right answer,dunno what they r trying to mean..
1
no see the question says that it retraces path afte third collision. somthing like above.
thus θ=30°
arka, how do you think it is 45.the reflection should take place after third collision, and in that diagram it retraced after the second collision itself.