Wavelength of light in vaccum is 5890 Å, then its wavelength in glass (`mu=1.5`) will be

Options

A. (a)`9372 Å`
B. (b)`7932 Å`
C. (c)`7548 Å`
D. (d)`3927 Å`

Answer

To find the wavelength of light in glass given its wavelength in vacuum and the refractive index of glass, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the given values**:
- Wavelength of light in vacuum (\( \lambda_{vacuum} \)) = 5890 Å (angstroms)
- Refractive index of glass (\( \mu \)) = 1.5

2. **Understand the relationship between wavelength in vacuum and wavelength in a medium**:
- The wavelength of light in a medium is given by the formula:
\[ \lambda_{medium} = \frac{\lambda_{vacuum}}{\mu} \]
- Here, \( \lambda_{medium} \) is the wavelength in the medium (glass in this case).

3. **Substitute the known values into the formula**:
- Using the formula, we substitute \( \lambda_{vacuum} \) and \( \mu \):
\[ \lambda_{glass} = \frac{5890 \, \text{Å}}{1.5} \]

4. **Perform the calculation**:
- Calculate \( \lambda_{glass} \):
\[ \lambda_{glass} = \frac{5890}{1.5} = 3926.67 \, \text{Å} \]
- Rounding off, we get:
\[ \lambda_{glass} \approx 3927 \, \text{Å} \]

5. **Conclusion**:
- The wavelength of light in glass is approximately 3927 Å.

### Final Answer:
The wavelength of light in glass is 3927 Å.