Rainbow is formed due to:

Question

What is the frequency of a wave with a wavelength of \( 2 \, \text{m} \) and a velocity of \( 4 \, \text{m/s} \)?

Answer 1

The correct answer to the question "Rainbow is formed due to:" is Total internal reflection & dispersion. Let me explain the step-by-step process of how a rainbow is formed:

Refraction: When sunlight enters a raindrop, it is refracted, or bent, because light travels at different speeds in different mediums. This refraction occurs at the surface of the raindrop.
Dispersion: As the light is refracted, it also disperses, meaning it splits into its constituent colors (red, orange, yellow, green, blue, indigo, violet). This is because different colors of light have different wavelengths and, hence, bend by different amounts upon entering the water droplet.
Total Internal Reflection: Once the dispersed light reaches the inside surface of the raindrop, it is reflected internally. This total internal reflection occurs because the angle of incidence inside is greater than the critical angle for water-air boundary, keeping the light trapped within the raindrop.
Refraction (again): As the light exits the raindrop, it is refracted again and continues to disperse further. This second refraction further enhances the separation of colors.
Observer’s Angle: Finally, the dispersed light reaches the observer’s eyes, but the observer will see only one color from each raindrop depending on the angle. Multiple raindrops contribute to the complete spectrum of colors as viewed in a circular arc—what we recognize as a rainbow.

This entire process, combining total internal reflection and dispersion, results in the formation of a rainbow. Other options listed like "Reflection only" and "Diffraction and dispersion" are incorrect because they do not account for the entire process that forms a rainbow. Reflection alone cannot create the color spectrum, and diffraction, which is the bending of waves around obstacles, is not the mechanism at play in rainbow formation.

Answer 2

The correct answer to the question "Rainbow is formed due to:" is Total internal reflection & dispersion. Let me explain the step-by-step process of how a rainbow is formed:

Refraction: When sunlight enters a raindrop, it is refracted, or bent, because light travels at different speeds in different mediums. This refraction occurs at the surface of the raindrop.
Dispersion: As the light is refracted, it also disperses, meaning it splits into its constituent colors (red, orange, yellow, green, blue, indigo, violet). This is because different colors of light have different wavelengths and, hence, bend by different amounts upon entering the water droplet.
Total Internal Reflection: Once the dispersed light reaches the inside surface of the raindrop, it is reflected internally. This total internal reflection occurs because the angle of incidence inside is greater than the critical angle for water-air boundary, keeping the light trapped within the raindrop.
Refraction (again): As the light exits the raindrop, it is refracted again and continues to disperse further. This second refraction further enhances the separation of colors.
Observer’s Angle: Finally, the dispersed light reaches the observer’s eyes, but the observer will see only one color from each raindrop depending on the angle. Multiple raindrops contribute to the complete spectrum of colors as viewed in a circular arc—what we recognize as a rainbow.

This entire process, combining total internal reflection and dispersion, results in the formation of a rainbow. Other options listed like "Reflection only" and "Diffraction and dispersion" are incorrect because they do not account for the entire process that forms a rainbow. Reflection alone cannot create the color spectrum, and diffraction, which is the bending of waves around obstacles, is not the mechanism at play in rainbow formation.

Rainbow is formed due to:

The Correct Option is B

Solution and Explanation

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