The refractive index of glass is 1.5. The speed of light in air is \(3 \times 10^8\) m/s. The speed of light in glass will be
Show Hint
- \(3 \times 10^8\) m/s
- \(2 \times 10^8\) m/s
- \(4.5 \times 10^8\) m/s
- \(2.25 \times 10^8\) m/s
The Correct Option is B
Solution and Explanation
Step 1: Understanding the Formula for Speed of Light in a Medium
The speed of light in any medium is given by the formula:
\[
v = \frac{c}{n}
\]
where:
- \(v\) is the speed of light in the medium
- \(c\) is the speed of light in vacuum (which is \(3 \times 10^8\) m/s)
- \(n\) is the refractive index of the medium
Step 2: Applying the Formula
Given that the refractive index of glass is \(n = 1.5\), and the speed of light in air is \(c = 3 \times 10^8\) m/s, we can calculate the speed of light in glass as:
\[
v = \frac{3 \times 10^8}{1.5} = 2 \times 10^8 \, \text{m/s}
\]
Step 3: Conclusion
Thus, the speed of light in glass is \(2 \times 10^8\) m/s. The correct answer is option (B).
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