Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
White light, such as sunlight, is not a single color but a mixture of seven different colors: Violet, Indigo, Blue, Green, Yellow, Orange, and Red, collectively known as .
Dispersion is the phenomenon of splitting of a beam of white light into its constituent colors when it passes through a transparent medium like a glass prism.
The band of seven colors produced by the dispersion of white light is called a spectrum.
In the spectrum, different colors bend at different angles. Red light bends the least, while Violet light bends the most.
A rainbow is a natural phenomenon caused by the dispersion of sunlight by tiny water droplets present in the atmosphere after rain. These droplets act like small prisms.
Newton's Disc is a circular disc with seven segments painted in the colors of . When rotated rapidly, the colors blend together due to the persistence of vision, making the disc appear white. This proves that white light consists of seven colors.
📐Formulae
💡Examples
Problem 1:
During the formation of a rainbow, what acts as the 'prism' to cause the dispersion of sunlight?
Solution:
Raindrops (water droplets).
Explanation:
After a rain shower, there are many tiny water droplets suspended in the air. When sunlight enters these droplets, they refract and disperse the light into its constituent seven colors (), then reflect it internally, and finally refract it again as it exits the droplet, forming a rainbow.
Problem 2:
Which color of the white light spectrum undergoes the maximum deviation when passing through a prism?
Solution:
Violet light.
Explanation:
In the process of dispersion, different colors travel at different speeds through the glass prism. Violet light has a shorter wavelength and slows down the most, resulting in the maximum angle of deviation, , compared to Red light, which has the longest wavelength and bends the least.