Question

please answer this question in detail

Answer 1

Apparent depth=real depth/n

Given apparent depth should be 21/2 and refractive index=4/3(n)

Substituting
$\frac{21}{2 } = \frac{real \: depth}{ \frac{4}{3} }$
$real \: depth = \frac{21 \times 4}{2 \times 3} = 14$

Given in Q that:
$3x - 1 = 14 \: \: \: \: so \: x = 5$
The value of x is 5....☺



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