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In figure, the optical fiber is l = 2 m long and has a diameter of d = 20 μ m. If a ray of light is incident on one end of the fiber at angle θ 1 = 40°, the number of reflections it makes before emerging from the other end is close to – (refractive index of fiber is 1.31 and sin 40° = 0.64) 40° d θ 2

1. 66000
2. 55000
3. 45000
4. 57000 CAREER POINT CAREER POINT , CP Tower, IPIA, Road No.1, Kota (Raj.), : 0744-6630500 | www.ecareerpoint.com Email: info@cpil.in Page # 2 JEE Main Online

Correct answer: 57000 CAREER POINT CAREER POINT , CP Tower, IPIA, Road No.1, Kota (Raj.), : 0744-6630500 | www.ecareerpoint.com Email: info@cpil.in Page # 2 JEE Main Online

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