First slide

Refraction of light

Question

An observer can see through a small hole on the side of a jar (radius 15 cm) at a point at height of 15 cm from the bottom (see figure). The hole is at a height of 45 cm. When the jar is filled with a liquid up to a height of 30 cm the same observer can see the edge at the bottom of the jar. If the refractive index of the liquid is N/100, where N is an integer, the value of N is ________

Moderate

Solution

$\begin{array}{l} In upper left triangle, tanr = \frac{15}{15} = 1 \\ \Rightarrow r = 45 ° \\ In lower right triangle, tani = \frac{15}{30} = \frac{1}{2} \\ \Rightarrow \sin i = \frac{1}{\sqrt{5}} \\ S n e l l' s L a w, (1) \sin r = (μ) \sin i \\ \Rightarrow 1 \frac{1}{\sqrt{2}} = μ \frac{1}{\sqrt{5}} \\ \Rightarrow μ = \sqrt{\frac{5}{2}} = 1.58 = \frac{158}{100} \end{array}$

Get Instant Solutions

When in doubt download our app. Now available Google Play Store- Doubts App

Recieve an sms with download link

Doubts App

OR

SCAN ME

Doubts App

Doubts App