Optics Wave Optics Mock Tests

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 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:

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'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:

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:

In a Young double slit experiment, a glass slab of thickness t and refractive index n is placed in front of one slit. The central maximum shifts by one fringe width β = λD/d. The thickness t of the glass slab 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 is much greater than d. If a thin film of thickness t and refractive index mu is placed in front of one slit, the fringe width:

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