Question

Which colour of the light has the longest wavelength?

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

Hint:

The order of colours in the visible light spectrum is violet, indigo, blue, green, yellow, orange, and red. 

Answer 1

The Correct Option is C

To determine which color of light has the longest wavelength, we need to consider the visible light spectrum. The visible light spectrum is a part of the electromagnetic spectrum that is visible to the human eye and ranges approximately from 380 nm to 750 nm in terms of wavelength.

The main colors in the visible light spectrum, listed here in order from shortest to longest wavelength, are:

• Violet - approximately 380 to 450 nm
• Blue - approximately 450 to 495 nm
• Green - approximately 495 to 570 nm
• Yellow - approximately 570 to 590 nm
• Orange - approximately 590 to 620 nm
• Red - approximately 620 to 750 nm

As depicted above, red light has the longest wavelength among the visible colors, approximately ranging from 620 nm to 750 nm. This is in contrast to violet light, which has the shortest wavelength.

Conclusion: The color of light with the longest wavelength is red. Hence, the correct answer is:

1. Red