The glancing angle in a X-ray diffraction is 30º and the wavelength of X-rays used is 20 nm. The inter planar spacing of the crystal dffracting these X-rays will be

The maximum distance between interatomic lattice planes is 15 Å. The maximum wavelength of X-rays which are diffracted by this crystal will be

If the X-ray tube is working at 20 kV then the minimum wavelength of X-rays will be

Ultraviolet radiation of 6.2 eV falls on an aluminium surface(work function 4.2 eV). The kinetic energy in joule of the faster electron emitted is approximately

The photoelectric threshold of Tungsten is 2300 Å. The energy of the electrons ejected from the surface by ultraviolet light of wavelength 1800 Å is

If the energy of a photon is 10 eV, then its momentum is