If stopping potentials corresponding to wavelengths `4000A` and `4500A` are 1.3 V and 0.9 V, respectively, then the work function of the metal isA. 0.3 eVB. 1.3 eVC. 2.3 eVD. 5 eV

If stopping potentials corresponding to wavelengths `4000A` and `4500A

1.	If stopping potentials corresponding to wavelengths `4000A` and `4500A` are 1.3 V and 0.9 V, respectively, then the work function of the metal isA. 0.3 eVB. 1.3 eVC. 2.3 eVD. 5 eV
Answer» Correct Answer - C `eV_S=(hc)/(lamda)-phi` or `eV_S+phi_0=(hc)/(lamda)` or `lamda=(hc)/(eV_S+phi_0)` `implies(lamda_2)/(lamda_1)=(eV_(S1)+phi_0)/(eV_(S2)+phi_0)` or `(4500)/(4000)=(1.3+phi_0)/(0.9+phi_0) ` or `phi_0=851.-9.xx0.9` Solving: `phi_0=(10.4-8.1)=2.3eV`

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If stopping potentials corresponding to wavelengths `4000A` and `4500A` are 1.3 V and 0.9 V, respectively, then the work function of the metal isA. 0.3 eVB. 1.3 eVC. 2.3 eVD. 5 eV

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