A) 32 Wm?2
B) 3 Wm?2
C) 8 Wm?2
D) 4 Wm?2
Correct Answer: B
Solution :
Angle between P1 and P2 = 30° (given) Angle between P2 and P3 = q = 90° ? 30° = 60° The intensity of light transmitted by P1 is \[{{I}_{1}}=\frac{{{I}_{0}}}{2}=\frac{32}{2}=16\frac{W}{{{m}^{2}}}\] According to Malus law the intensity of light transmitted by P2 is \[{{I}_{2}}={{I}_{1}}{{\cos }^{2}}30{}^\circ =16\,{{\left( \frac{\sqrt{3}}{2} \right)}^{2}}=12\,\frac{W}{{{m}^{2}}}\] Similarly intensity of light transmitted by P3 is \[{{I}_{3}}={{I}_{2}}{{\cos }^{2}}\theta =12{{\cos }^{2}}60{}^\circ =12\,{{\left( \frac{1}{2} \right)}^{2}}=3\frac{W}{{{m}^{2}}}\]You need to login to perform this action.
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