The electron emitted from an electron *** are having 2 eV of kinetic energy, then are accelerated by applying a potential of V volts and are allowed to fall on atomic hydrogen gas. It has been observed that red light of wavelength 656.3 nm has been emitted by the hydrogen. Assume that total energy of electron has been given, then V has the value given by
(a) 2 V
(b) 0.11 V
(c) -2 V
(d) -0.11 V
