A ray of light is incident at an angle of 30º on a glass prism of refractive index 1.5. Calculate the angle through which the ray is minimally deviated in the prism. (The medium surrounding the prism is air)

seekahi

5 years ago

Required is Minimum Deviation, Dm ( with 'm' written as subscript).

In any case the answer is only half inaccurate as,

Dm = 2(i - r) ..................recall that at min deviation, for a glass prism experiencing double refraction,

i = ½ [A + Dm] for A = 2r or, r = ½A

putting these together proves that ,

Dm = 2(i - r) with i = 30 deg and r as found overleaf
already = 19.47 deg

= 2 ( 30 - 19.47) deg
= 21.1 deg (approx) matching with OPTION C

THANK YOU FOR LEARNING

alvan1

2 years ago

Wrong, correct answer is option C.
For Minimum deviation we use n = A+d/2 ÷A/2

Ikpevictor1

4 years ago

my school is perfectly correct

Alisha101

2 years ago

Is this another new formula to solve this because the formula I know is refractive index=sin1/2(A+D)/sin1/2A and D= 2i-A
Please review and correct me if I am wrong

ayomideadekunle275

11 months ago

solve this for me

Cho123

4 months ago

Answer not in the option