Optics Wave Optics Mock Tests

In a Young double slit experiment, the slit separation is d and the screen is at distance D from the slits (D ≫ d). If the wavelength is changed from λ to λ + Δλ (where Δλ ≪ λ), the shift in the position of the m-th bright fringe is approximately:

Unpolarized light of intensity I₀ passes through three polaroids arranged in sequence. The first polaroid has its transmission axis vertical. The third has its transmission axis horizontal. The second polaroid is placed between them with its transmission axis at an angle θ to the vertical. The intensity of light emerging from the third polaroid is maximum when θ equals:

In a Young double slit experiment, the slits are separated by distance d and the screen is at distance D (D >> d). A thin glass slab of thickness t and refractive index μ is placed in front of one slit. If the central maximum shifts by a distance equal to the fringe width, the thickness t is:

Light is incident normally on a thin film of thickness t and refractive index μ in air. The reflected light shows a maximum at wavelength λ₁ and a minimum at λ₂ (λ₂ < λ₁), with no other extrema between them. The thickness t is:

A single slit of width a is illuminated by monochromatic light of wavelength lambda. The first minimum in the diffraction pattern occurs at an angle theta_1. If the slit width is doubled, the new angle of the first minimum is:

In a double-slit experiment, the intensity at the central maximum is I_0. If one of the slits is covered, the intensity at the same point becomes:

In a Young's double slit experiment, the slits are separated by 0.5 mm and the screen is 1.0 m away. If the wavelength of light used is 500 nm, the distance between the central maximum and the 5th bright fringe is:

In a Young double slit experiment, the slits are separated by distance d and the screen is at distance D from the slits (D >> d). A thin glass slab of refractive index mu and thickness t is placed in front of one of the slits. The fringe width remains beta = lambda*D/d. The number of fringes shifted on the screen is: