In refraction, light waves are bent on passing from one medium to the second medium, because, in the second medium

Options

A. the frequency in different
B. the coeficient of elasticity is different
C. the speed is different.
D. the amplitude is smaller.

Answer

To solve the question regarding why light waves are bent when passing from one medium to another during refraction, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Refraction**: Refraction occurs when light travels from one medium to another, causing a change in its speed and direction. This bending of light is influenced by the properties of the two media involved.

2. **Identify the Factors Affecting Refraction**: The primary factors that affect how light behaves during refraction are the refractive indices of the two media. The refractive index (n) is a measure of how much the speed of light is reduced in a medium compared to its speed in a vacuum.

3. **Consider the Options Provided**:
- **Option A**: Frequency is different - This is incorrect because the frequency of light remains constant when it passes from one medium to another.
- **Option B**: Coefficient of elasticity is different - While this can affect the speed of sound, it is not directly relevant to the bending of light in the context of refraction.
- **Option C**: Speed is different - This is correct. The speed of light changes as it enters a different medium, which causes it to bend.
- **Option D**: Amplitude is smaller - Amplitude does not affect the bending of light during refraction.

4. **Conclusion**: Since the speed of light is different in the two media, this difference in speed is the reason why light waves bend when transitioning from one medium to another. Therefore, the correct answer is **Option C**: The speed is different.

### Final Answer:
The light waves are bent on passing from one medium to the second medium because in the second medium, the **speed is different**.

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