Upon being struck by 240-nm photons,a metal ejects electrons with a maximum kinetic energy of
1) 45 eV.What is the work function of this metal? (h = 6.626 × 10^-34 J • s,c = 3.00 × 10⁸ m/s,
1 eV = 1.60 × 10^-19 J)

Question

Quizplus · Accepted Answer

Explanation:The work function of a metal is the minimum energy required to remove an electron from the metal. The maximum kinetic energy of the ejected electrons is given by:$$KE_{max} = h
u - \phi$$where:$$h$$ is Planck's constant$$
u$$ is the frequency of the incident photons$$\phi$$ is the work function of the metalWe can rearrange this equation to solve for the work function:$$\phi = h
u - KE_{max}$$Plugging in the given values, we get:$$\phi = (6.626 	imes 10^{-34} J \cdot s)(3 	imes 10^8 m/s)/(240 	imes 10^{-9} m) - (45 eV)(1.60 	imes 10^{-19} J/eV)$$$$\phi = 3.73 eV$$Therefore, the work function of the metal is 3.73 eV.

Upon Being Struck by 240-Nm Photons,a Metal Ejects Electrons with a Maximum