Question 325: Ray Optics

Question

A prism of angle A = 1o has a refractive index
$$\mu $$ = 1.5. A good estimate for the minimum angle
of deviation (in degrees) is close to $${N \over {10}}$$.
Value of N is ____.

Accepted Answer

Deviation for small-angled prism is given by
$$\delta$$ = ($$\mu$$ $$-$$ 1) A
Given, A = 1$$^\circ$$, $$\mu$$ = 1.5
Substituting these values in above equation, we get
$$\delta$$ = (1.5 $$-$$ 1)1 $$\delta$$ = 0.5
According to question, $$\delta  = {N \over {10}}$$
$$ \Rightarrow 0.5 = {N \over {10}} = N = 5$$
Hence, the value of N is 5.

Ray Optics

A prism of angle A = 1o has a refractive index $\mu = 1.5. A good estimate for the minimum angle of deviation (in degrees) is close to {N \over {10}}$. Value of N is ____.

Choose the correct answer: