The colour are characterized by which of following character of light-

Options

A. Frequency
B. Amplitude
C. Wavelength
D. velocity

Answer

To solve the question regarding which characteristic of light is used to define colors, we can analyze the options provided: frequency, amplitude, wavelength, and velocity.

### Step-by-Step Solution:

1. **Understanding the Options**:
- **Frequency**: This is defined as the number of cycles of a wave that pass a point in one second. For white light, which consists of multiple colors, the frequency of all colors is not the same.
- **Amplitude**: This refers to the height of the wave and is related to the intensity of light. However, amplitude does not determine the color of light.
- **Wavelength**: This is the distance between successive peaks of a wave. Different colors of light correspond to different wavelengths. For example, red light has a longer wavelength than blue light.
- **Velocity**: The speed of light in a vacuum is constant, but it can change when light travels through different media. The velocity of light can be expressed as the product of frequency and wavelength (v = fλ).

2. **Analyzing Each Characteristic**:
- Since the frequency of light does not vary among the colors of white light, it cannot be used to characterize color.
- Amplitude relates to brightness, not color.
- Wavelength varies for different colors, making it a suitable characteristic for defining color.
- Velocity, while related to wavelength and frequency, does not directly characterize color since it is constant in a vacuum.

3. **Conclusion**:
- The characteristic that best defines the color of light is **wavelength**. Different colors correspond to different wavelengths of light.

### Final Answer:
The colors are characterized by the **wavelength** of light.

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