Question

please tell fast
In a hurry​

Answer 1

Explanation:

We know that refractive index of light is defined by

$n = \frac{speed \: of \: light \: in \: vaccum}{speed \: of \: light \: that \: medium}$

$n = \frac{3 \times 10 {}^{8} }{v} = 1.5$

$v = 2 \times 10 {}^{8}m/s$

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