Wavelength of visible light/PAR is

Options

A. 200-400 nm
B. 400-700 nm
C. 700-900 nm
D. 100-200 nm.

Answer

To determine the wavelength of visible light or Photosynthetically Active Radiation (PAR), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Concept of PAR**:
- PAR stands for Photosynthetically Active Radiation, which refers to the portion of the light spectrum that plants can use for photosynthesis.

2. **Identify the Range of Wavelengths**:
- The visible light spectrum, which is also the range of PAR, includes wavelengths from approximately 400 nanometers (nm) to 700 nanometers (nm).

3. **List the Colors of Visible Light**:
- Within this range, the colors of visible light are organized as follows:
- Violet: ~400 nm
- Indigo: ~450 nm
- Blue: ~475 nm
- Green: ~500 nm
- Yellow: ~570 nm
- Orange: ~590 nm
- Red: ~700 nm

4. **Conclude the Wavelength Range**:
- Therefore, the complete range of wavelengths for visible light or PAR is from 400 nm to 700 nm.

5. **Select the Correct Answer**:
- Based on the information provided, the correct answer to the question is that the wavelength of visible light/PAR is from 400 nm to 700 nm.

### Final Answer:
The wavelength of visible light/PAR is **400 to 700 nanometers**.

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