Diffraction

Definition: Diffraction is the bending of waves around obstacles and the spreading of waves as they pass through an opening or aperture.

Types of Diffraction:

1. Fraunhofer Diffraction: Occurs when light waves are diffracted by a single slit or aperture.
2. Fresnel Diffraction: Occurs when light waves are diffracted by an obstacle or by multiple slits.

Factors Affecting Diffraction:

• Wavelength: Shorter wavelengths result in less diffraction, while longer wavelengths result in more significant diffraction.
• Size of the Opening or Obstacle: Smaller openings or obstacles result in more significant diffraction, while larger openings or obstacles result in less diffraction.
• Distance from the Source: The distance from the source of the waves affects the degree of diffraction observed.

Applications of Diffraction:

• Diffraction Grating: Used in spectroscopy to disperse light into its component wavelengths.
• X-ray Diffraction: Used to study the structure of crystalline materials, including biological molecules such as DNA and proteins.
• Acoustic Diffraction: Used to design concert halls and auditoriums for optimal sound distribution.

Study Guide:

1. Define diffraction and explain its significance in the behavior of waves.
2. Compare and contrast Fraunhofer and Fresnel diffraction, providing examples of each type.
3. Discuss the factors that affect the degree of diffraction observed, and provide real-life examples of how these factors can be manipulated for practical applications.
4. Explore the various applications of diffraction in different scientific and engineering fields, and explain the specific principles that make these applications possible.
5. Conduct experiments to demonstrate diffraction using different types of waves (e.g., light, sound) and different types of obstacles or openings.