The refractive index of diamond is 2.419. If the speed of light in vacuum is $3 \times 10^8$ m s$^{-1}$, then the speed of light in diamond is
Show Hint
- $1.240 \times 10^8$ m s$^{-1}$
- $1.352 \times 10^8$ m s$^{-1}$
- $1.521 \times 10^8$ m s$^{-1}$
- $2.433 \times 10^8$ m s$^{-1}$
The Correct Option is A
Solution and Explanation
Refractive index $n = \frac{c}{v}$ where c = speed of light in vacuum, v = speed in the medium.
Step 2: Substitute values.
$v = \frac{c}{n} = \frac{3 \times 10^8}{2.419}$.
Step 3: Perform calculation.
$v \approx 1.240 \times 10^8$ m s$^{-1}$.
Step 4: Conclusion.
Thus, light travels at $1.240 \times 10^8$ m/s in diamond.
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