**Category:** Optics  
**Subtype:** Refraction and Frequency of Light  
**Problem Description:** This problem involves the behavior of light as it transitions from a vacuum into a transparent liquid with a specific refractive index. The task is to determine the color and frequency of the light in the liquid.

**Key Points:**
- The light is monochromatic orange with frequency \( f \).
- The refractive index of the liquid is \( n = 1.5 \).
- The problem asks about the color and frequency of the light in the liquid after refraction. 

**Concepts Involved:**
- When light enters a medium with a different refractive index, its speed changes, but its frequency remains constant. The wavelength changes according to the refractive index.
- The color of light is determined by its frequency, and since the frequency does not change, the color will remain the same.

**Conclusion:** The light will remain orange with the same frequency \( f \) in the liquid.