A beam of electrons of energy E scatters from a target having atomic specing of 1Å. The first maximum intensity occurs at `theta = 60^@`. The E (in eV) is ___________
(Planck constant `h = 6.64 xx 10^(-34) Js`,
`1eV = 1.6 xx 10^(19)J`,
electron mass `m = 9.1 xx 10^(-31) kg`)

Light of wavelength 3000 Å falls on a metal surface having work function 2.3 eV. Calculate the maximum velocity of ejected electrons. (Planck's constant , h = 6.63 xx 10 ^( - 34 ) J.s. , velocity of light c = 3 xx10 ^( 8 ) m//s , mass of an electron = 9.1 xx 10 ^( -31 ) kg )

The kinetic energy of an electron is 4.55 xx 10^(-25)J . Calculate the wavelength . [h = 6.6 xx 10^(-34)Js , mass of electron = 9.1 xx 10^(-31)kg]

Calculate the radius of the first and second orbit of sodium atom (Z=11) . (h=6.6xx10^(-34) J s, e=1.6xx10^(-19) C and m=9.1xx10^(-31) kg.)

If the work function of a and is 3 eV, calculate the threshold wavelength of that metal. (Velocity of light =3xx10^(8)m//s Planck's constant= 6.63xx10^(-34)J-s,1eV=1.6xx10^(-19) )

An electron beam has a kinetic energy equal to 100 eV . Find its wavelength associated with a beam , if mass of electron = 9.1 xx 10^(-31) " kg and 1 eV " = 1.6 xx 10^(-19) J . (Planks's constant = 6.6 xx 10^(-34) J-s)

If de Broglie wavelength of an electron is 0.5467 Å, find the kinetic energy of electron in eV. Given h=6.6xx10^(-34) Js , e= 1.6xx10^(-19) C, m_e=9.11xx10^(-31) kg.

The electric field of certain radiation is given by the equation E = 200 {sin (4pi xx 10^10)t + sin(4pi xx 10^15)t} falls in a metal surface having work function 2.0 eV. The maximum kinetic energy 2.0 eV. The maximum kinetic energy (in eV) of the photoelectrons is [Plank's constant (h) = 6.63 xx 10^(-34)Js and electron charge e = 1.6 xx 10^(-19)C]

In an atom , an electron is moving with a speed of 600 m/s with an accuracy of 0.05% . The certainty with which the position of the electron can be located is (h = 6.6 xx 10^(-34) kgm^(2)s^(-1) , mass of electron , e_(m) = 9.1 xx 10^(-31) kg ):