Which of the following properties of light conclusively support wave theory of light?

Options

A. Light obeys laws of reflection
B. speed of light in water is smaller then the speed in vacuum.
C. Light shows interference
D. Light shows photoelectric effect.

Answer

To determine which properties of light conclusively support the wave theory of light, we can analyze the options provided in the question. Here’s a step-by-step solution:

### Step 1: Understand the Wave Theory of Light
The wave theory of light posits that light behaves as a wave, exhibiting properties such as interference, diffraction, and polarization.

**Hint:** Recall the fundamental principles of wave behavior, such as superposition and interference patterns.

### Step 2: Analyze the Properties of Light
1. **Interference**: This phenomenon occurs when two or more light waves overlap, resulting in a new wave pattern. It is a definitive characteristic of wave behavior.

**Conclusion**: Interference supports the wave theory of light.

2. **Reflection**: Light obeying the laws of reflection (angle of incidence equals angle of reflection) is a property that can be observed in both waves and particles. Thus, it does not exclusively support the wave theory.

**Conclusion**: Reflection does not conclusively support the wave theory of light.

3. **Refraction**: The bending of light when it passes from one medium to another (e.g., from air to glass) is due to a change in speed. This behavior is explained by the wave theory, as it involves the change in wavelength and speed of light in different media.

**Conclusion**: Refraction supports the wave theory of light.

4. **Photoelectric Effect**: This phenomenon, where light ejects electrons from a material, supports the particle theory of light, as it cannot be explained by wave theory alone.

**Conclusion**: The photoelectric effect does not support the wave theory of light.

### Step 3: Summarize the Findings
From the analysis:
- **Interference**: Supports wave theory.
- **Reflection**: Does not conclusively support wave theory.
- **Refraction**: Supports wave theory.
- **Photoelectric Effect**: Does not support wave theory.

### Final Answer
The properties of light that conclusively support the wave theory of light are **Interference** and **Refraction**.

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