The wavelengths of violet and red ends of visible spectrum are 390nm and 780 nm respectively. Evaluate the energy range of the photons of the visible light in electron volts.

Calculate the frequency and energy of a photon of wavelength 589 nm.

Calculate the mass of a photon of light of wavelength 580 nm.

Calculate energy in terms of blue light of wavelength 450 nm.

Calculate the frequency of visible light of wavelength 650 nm.

Calculate the energy of an electron moving with a wavelength of 525 nm.

A photon of wavelength 450 nm strikes a metal surface whose work function is 2.5 eV. Calculate the energy of the photon

The work function for Caesium atom is 1.9 eV. Calculate the threshold wavelength of the radiation. If Caesium is irradiated with a wavelength 500 nm, calculate the kinetic energy and the velocity of the ejected electron.