Question:

A metal surface is illuminated by light of two different wavelengths248nmand310nm. The maximum speeds of the photoelectrons corresponding to these wavelengths areu1andu2, respectively. If the ratiou1:u2=2:1andhc=1240eVnm, the work function of the metal is nearly :3.7eV3.2eV2.8eV2.5eVA metal surface is illuminated by light of two different wavelengths248nmand310nm. The maximum speeds of the photoelectrons corresponding to these wavelengths areu1andu2, respectively. If the ratiou1:u2=2:1andhc=1240eVnm, the work function of the metal is nearly :3.7eV3.2eV2.8eV2.5eV248nm248nm248nm248248nnmm310nm310nm310nm310310nnmmu1u1u1u1uuu111u2u2u2u2uuu222u1:u2=2:1u1:u2=2:1u1:u2=2:1u1uuu111::u2uuu222==22::11hc=1240eVnmhc=1240eVnmhc=1240eVnmhhcc==12401240eeVVnnmm3.7eV3.7eV3.7eV3.7eV3.73.7eeVV3.2eV3.2eV3.2eV3.2eV3.23.2eeVV2.8eV2.8eV2.8eV2.8eV2.82.8eeVV2.5eV2.5eV2.5eV2.5eV2.52.5eeVVA2.8eV2.8eV2.8eV2.8eV2.8eV2.82.8eeVVB2.5eV2.5eV2.5eV2.5eV2.5eV2.52.5eeVVC3.7eV3.7eV3.7eV3.7eV3.7eV3.73.7eeVVD3.2eV3.2eV3.2eV3.2eV3.2eV3.23.2eeVV?