A microscope is focused on an object at the bottom of a bucket. If liquid with refractive index $\frac{5}{3}$ is poured inside the bucket, then the microscope has to be raised by $30 \mathrm{~cm}$ to focus the object again. The height of the liquid in the bucket is :
Solution
Shift $=\left(d-\frac{d}{\mu}\right)=30 \mathrm{~cm}$
<br/><br/>$$
\begin{aligned}
& \Rightarrow d\left[1-\frac{1}{\frac{5}{3}}\right]=30 \\\\
& \Rightarrow d=\frac{30 \times 5}{2}=75 \mathrm{~cm}
\end{aligned}
$$
About this question
Subject: Physics · Chapter: Optics · Topic: Refraction and Snell's Law
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