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Solve question 10

**10. **A ray incident at an angle 53$\xb0$ on a prism emerges at an angle at 37$\xb0$ as shown. If the angle of incidence is made 50$\xb0$, which of the following is a possible value of the angle of emergence.

(A) 35$\xb0$ (B) 42$\xb0$ (C) 40$\xb0$ (D) 38$\xb0$

i + e = A + d (d is angle of deviation)

In the first case, i +e =90 (53+37)

Hence A+d=90

d is a characteristic of the corresponding wavelength of light in the material of prism of some refractive index.

Since here we are using the same light wave, the

**d**remains constant.

**A**is the Angle of Prism and is constant.

Thus

**A+d**remains constant. SInce its initial value was 90, its final value will be 90 too.

Thus according to Prism Law

**i+e**should be equal to A+d thus equal to 90

In second case, i=50

i+e=90

e=90-50

e=40

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