WBJEE 2025 Physics and Chemistry Papers

An electron in Hydrogen atom jumps from the second Bohr orbit to the ground state and the difference between the energies of the two states is radiated in the form of a photon. This photon strikes a material. If the work function of the material is 4.2 eV , then the stopping potential is (Energy of electron in n-th orbit =−‌

13⋅6

n2

‌eV )