Dispersion of Light

  1. Dispersion is the phenomenon where white light splits into its constituent colors when it passes through a prism.
  2. It occurs due to the variation in the refractive index of the material for different wavelengths of light.
  3. The order of colors in the visible spectrum is: Violet, Indigo, Blue, Green, Yellow, Orange, Red (VIBGYOR).
  4. Isaac Newton was the first to demonstrate dispersion using a glass prism.
  5. The angle of deviation is different for each color, with violet deviating the most and red the least.

Prism and Light Behavior

  1. A prism is a transparent optical element with flat, polished surfaces that refract light.
  2. The splitting of light occurs due to the refraction at both surfaces of the prism.
  3. The angle of prism and its material affect the extent of dispersion.
  4. The refractive index of a medium is wavelength-dependent, causing the dispersion of different colors.
  5. The phenomenon can be used to demonstrate the composition of white light.

Visible Spectrum

  1. The visible spectrum is the portion of the electromagnetic spectrum that is visible to the human eye.
  2. It ranges approximately from 380 nm (violet) to 750 nm (red).
  3. The wavelength increases from violet to red, while the frequency decreases.
  4. The energy of light decreases with increasing wavelength in the visible spectrum.
  5. The visible spectrum is just a small part of the electromagnetic spectrum, which includes other forms like infrared, ultraviolet, etc.

Applications of Dispersion

  1. Dispersion explains the formation of rainbows in the atmosphere due to water droplets acting as prisms.
  2. It is utilized in devices like spectrometers to study the properties of light.
  3. The phenomenon helps in understanding the nature and wavelengths of light emitted by various sources.
  4. Used in prism-based optical instruments for scientific and educational purposes.
  5. Provides insights into the structure of materials and their interaction with light.

Important Notes for Competitive Exams

  1. Understand the concept of refractive index and its role in dispersion.
  2. Memorize the order of colors in the visible spectrum (VIBGYOR).
  3. Practice problems involving the angle of deviation and dispersion in a prism.
  4. Revise the relationship between wavelength, frequency, and energy of light.
  5. Be familiar with applications of dispersion in rainbows and optical instruments.

Category

Questions

  1. The bending of light when it passes from one medium to another is known as:
  2. In a double rainbow, the secondary rainbow is formed due to:
  3. Which phenomenon explains why the sky appears red during sunrise and sunset?
  4. What causes the different bending angles for different colors in a prism?
  5. What is the role of a prism in a spectrometer?
  6. The refractive index of a medium is highest for which color of light?
  7. Which phenomenon causes the blue color of the sky?
  8. The scattering of light depends on:
  9. Which color of light is scattered the least by the atmosphere?
  10. Which light has the longest wavelength in the visible spectrum?
  11. Which phenomenon forms a spectrum of colors in thin oil films?
  12. The phenomenon of dispersion is commonly used in which device?
  13. What is the wavelength of red light in the visible spectrum?
  14. A prism splits white light into different colors because:
  15. Which phenomenon is responsible for the red color of the sun at sunrise and sunset?
  16. Which scientist first explained the dispersion of light through a prism?
  17. The visible spectrum is a part of:
  18. Why does dispersion not occur in a glass slab?
  19. Dispersion occurs because different colors of light:
  20. The angle of minimum deviation in a prism is minimum for which color?
  21. What happens to the speed of light when it passes through a denser medium?
  22. In a prism, the angle between the incident and emergent rays is called:
  23. Why does violet light deviate more than red light in a prism?
  24. Which part of the electromagnetic spectrum is visible to the human eye?
  25. The phenomenon responsible for the formation of a rainbow is:
  26. What is the wavelength range of visible light?
  27. The splitting of white light into its component colors in a prism is due to:
  28. How many colors are present in the visible spectrum of light?
  29. What is the order of colors in the visible spectrum starting from the top?
  30. Which color of light deviates the least in a prism?
  31. Which color of light deviates the most in a prism?
  32. Which optical phenomenon occurs in a prism to cause dispersion?
  33. What is dispersion of light?
  34. What is the shape of the spectrum obtained after dispersion through a prism?
  35. Why is a prism able to disperse light?
  36. What is the purpose of a spectrometer?
  37. Which phenomenon does not contribute to the formation of a rainbow?
  38. The visible spectrum is also known as:
  39. What is the approximate wavelength of green light in the visible spectrum?