A Hydrogen-like atom has atomic number \( Z \). Photons emitted in the electronic transitions from level \( n = 4 \) to level \( n = 3 \) in these atoms are used to perform photoelectric effect experiment on a target metal. The maximum kinetic energy of the photoelectrons generated is \( 1.95 \, \text{eV} \). If the photoelectric threshold wavelength for the target metal is \( 310 \, \text{nm} \), the value of \( Z \) is ______.
[Given: \( hc = 1240 \, \text{eV} \! \cdot \! \text{nm} \) and \( Rhc = 13.6 \, \text{eV} \), where \( R \) is the Rydberg constant, \( h \) is the Planck’s constant and \( c \) is the speed of light in vacuum]
