In a diffraction pattern due to a single slit of width a with incident light of wavelength $\lambda \backslash lambda$, at an angle of diffraction $\theta \backslash theta$, the condition for the first minimum is

The fringes produced in a diffraction pattern are of

For a single slit of width a, the first diffraction maximum with light of wavelength $\lambda \backslash lambda$ subtends an angle $\theta \backslash theta$ such that sin $\theta \backslash theta$ is equal to

A parallel beam of light ($\lambda \backslash lambda$ = 5000 Å) is incident normally on a narrow slit of width 0.2 mm. The Fraunhofer diffraction pattern is observed on a screen placed at the focal plane of a convex lens (f = 20 cm). The first two minima are separated by

A plane wave of wavelength 5500 Å is incident normally on a slit of width $2\times 10^{-2}2\; \backslash times\; 10^\{-2\}$ cm. The width of the central maximum on a screen 50 cm away is 

If the numerical aperture of a microscope is increased, then its

The resolving power of a refracting telescope is increased by

The resolving power of a telescope of aperture 100 cm, for light of wavelength $5.5\times 10^{-7}m5.5\; \backslash times\; 10^\{-7\}m$ is 

The resolving power of a telescope depends upon the

If a is the aperture of a telescope and 2 is the wavelength of light then the resolving power of the telescope is