Which colour of the light has the longest wavelength?

Options

A. violet
B. red
C. blue
D. green

Explanation

To determine which color of light has the longest wavelength, we can follow these steps:

### Step 1: Understand the Visible Spectrum
The visible spectrum of light consists of seven colors, which are typically remembered by the acronym ROYGBIV: Red, Orange, Yellow, Green, Blue, Indigo, and Violet.

### Step 2: Know the Order of Wavelengths
In the visible spectrum, the colors are arranged in order of increasing wavelength. This means that:
- Violet has the shortest wavelength.
- Red has the longest wavelength.

### Step 3: Identify the Color with the Longest Wavelength
From the order of colors, we can conclude that red light has the longest wavelength compared to the other colors in the visible spectrum.

### Conclusion
Thus, the color of light that has the longest wavelength is **Red**.

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