What is the primary source of UV rays?

Options

A. Oscillation of electrons
B. Due to Eddy Currents
C. Vibration of molecules
D. Jumping of electrons in inner shells

Explanation

**Step-by-Step Solution:**

1. **Understanding UV Rays**: Ultraviolet (UV) rays are a type of electromagnetic radiation with wavelengths shorter than visible light but longer than X-rays. They are known for their ability to cause chemical reactions and are present in sunlight.

2. **Identifying the Source**: To determine the primary source of UV rays, we need to examine the options provided:
- **Option 1: Oscillation of electrons** - While oscillating electrons can produce electromagnetic radiation, they do not specifically produce UV rays.
- **Option 2: Eddy currents** - Eddy currents are loops of electric current induced within conductors by a changing magnetic field, but they are not a source of UV radiation.
- **Option 3: Vibration of molecules** - Molecular vibrations can produce infrared radiation, not UV rays.
- **Option 4: Jumping of electrons in inner shells** - When electrons transition between energy levels (specifically from higher energy levels to lower energy levels), they emit photons. If this transition occurs in the ultraviolet range, it results in the emission of UV rays.

3. **Conclusion**: Based on the analysis of the options, the primary source of UV rays is the jumping of electrons in inner shells (Option 4).

**Final Answer**: The primary source of UV rays is the jumping of electrons in inner shells.

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