The radiation corresponding to the transition of hydrogen atom falls on a metal surface to produce photoelectrons. These electrons are made to enter an electric field of as shown in the figure. If the electrons just change their direction of motion after 1 second, then the work function of the metal is close to which of the following choices?
Details and Assumptions:
Take the mass of electron, ,
The charge on electron, and .
The Ionization energy of Hydrogen atom in ground state is