Shortcut Methods
Typical numericals on Fringe Shift in the Two-hole Interference Equipment for JEE and CBSE board exams:
- Two-hole interference with monochromatic light: Shortcut: To calculate the fringe width for monochromatic light, use the formula β = λD/d, where λ is the wavelength of light, D is the distance between the screen and the slits, and d is the distance between the slits.
Formula: β = λD/d β: Fringe width (in meters) λ: Wavelength of light (in meters) D: Distance between the screen and the slits (in meters) d: Distance between the slits (in meters)
- Two-hole interference with white light: Shortcut: To calculate the overlap of central bright fringes for red and violet light, use the formula Δy = (λred - λviolet) D/d, where λred and λviolet are the wavelengths of red and violet light, respectively, D is the distance between the screen and the slits, and d is the distance between the slits.
Formula: Δy = (λred - λviolet) D/d Δy: Overlap of central bright fringes for red and violet light (in meters) λred: Wavelength of red light (in meters) λviolet: Wavelength of violet light (in meters) D: Distance between the screen and the slits (in meters) d: Distance between the slits (in meters)
- Effect of wavelength on fringe width: Shortcut: To calculate the fringe width for different wavelengths of light, use the formula β = λD/d, where λ is the wavelength of light, D is the distance between the screen and the slits, and d is the distance between the slits.
Formula: β = λD/d β: Fringe width (in meters) λ: Wavelength of light (in meters) D: Distance between the screen and the slits (in meters) d: Distance between the slits (in meters)
- Effect of slit separation on fringe width: Shortcut: To calculate the fringe width for different slit separations, use the formula β = λD/d, where λ is the wavelength of light, D is the distance between the screen and the slits, and d is the distance between the slits.
Formula: β = λD/d β: Fringe width (in meters) λ: Wavelength of light (in meters) D: Distance between the screen and the slits (in meters) d: Distance between the slits (in meters)
- Determination of wavelength using two-hole interference: Shortcut: To calculate the wavelength of light using two-hole interference, use the formula λ = βD/d, where β is the fringe width, D is the distance between the screen and the slits, and d is the distance between the slits.
Formula: λ = βD/d λ: Wavelength of light (in meters) β: Fringe width (in meters) D: Distance between the screen and the slits (in meters) d: Distance between the slits (in meters)