Hydrogen electron jumps from n to the ground state and irradiates material of work function 2.75 eV. If its stopping potential is 10 eV (equivalent stopping energy), n is:
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Hydrogen electron jumps from n to the ground state and irradiates material of work function 2.75 eV. If its stopping potential is 10 eV (equivalent stopping energy), n is:

G1 Physics · Accepted Answer

Photon energy Eγ = W + Kₘₐₓ = 2.75 + 10 = 12.75 eV. For n→1, 13.6(1 − 1/n²) = 12.75. Therefore 1/n² = 1 − 12.75/13.6 = 1/16, so n = 4. Answer: B.