The refractive index of glass is 1.5 for light waves of `lamda=6000` Ã… in vacuum. Its wavelength in glass is

Options

A. 2000 Ã…
B. 4000 Ã…
C. 1000 Ã…
D. 3000 Ã…

Explanation

To find the wavelength of light in glass, we will use the relationship between the refractive index, the wavelength in vacuum, and the wavelength in the medium (glass in this case).

### Step-by-Step Solution:

1. **Identify the Given Quantities**:
- Refractive index of glass, \( \mu = 1.5 \)
- Wavelength of light in vacuum, \( \lambda_v = 6000 \, \text{Å} \) (angstroms)

2. **Use the Relationship Between Wavelengths and Refractive Index**:
The relationship between the wavelength in vacuum and the wavelength in a medium is given by:
\[ \lambda_g = \frac{\lambda_v}{\mu} \]
where:
- \( \lambda_g \) is the wavelength in glass,
- \( \lambda_v \) is the wavelength in vacuum,
- \( \mu \) is the refractive index of the medium.

3. **Substitute the Known Values**:
Substitute the values into the equation:
\[ \lambda_g = \frac{6000 \, \text{Å}}{1.5} \]

4. **Perform the Calculation**:
- First, divide \( 6000 \) by \( 1.5 \):
\[ \lambda_g = \frac{6000}{1.5} = 4000 \, \text{Å} \]

5. **Final Result**:
The wavelength of light in glass is:
\[ \lambda_g = 4000 \, \text{Å} \]

### Summary:
The wavelength of light in glass is \( 4000 \, \text{Å} \).