Question

15. The speed of light in a certain glass is 1.8 x 10 m/sec, the refractive
index of the glass is
1.87
b. 1.67
c. 1.25
d. 2.87​

Answer 1

$\tt \green{given : \bigstar \: the \: speed \: of \: light \: in \: a \: certain \: glass \: is \: 1.8 \times 10m \sec} \\ \tt \red{too \: find : \dag \: the \: refractive \: index \: of \: the \: glass } \\ \tt \blue{sol {}^{n} : } \\ \tt \purple{we \: kno w \: that \: n_{m} = \frac{c}{v} } \\ \tt \purple{so...c = 3 \times 10 {}^{8} m \sec} \\ \tt \purple{ n_{m} = \frac{3 \times 10 {}^{8}}{1.8 \times 10} } \\ \tt \purple{n_{m} = 1.67}$

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