The work funciton of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectron emission from this substance is approximately

The work funciton of a substance is 4.0 eV. The longest wavelength of

1.	The work funciton of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectron emission from this substance is approximately
Answer» 540 NM 400 nm 310 nm 220 nm Solution :`lambda_(0) = (hc)/(W) = (6.63 xx 10^(-34) xx 3 xx 10^(8))/(4.0 xx 1.6 xx 10^(-19)) m = 310 xx 10^(-9) m = 310` nm

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The work funciton of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectron emission from this substance is approximately

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