Photoelectric effect: Upon being struck by 240-nm photons, a metal ejects electrons with a maximum kinetic energy of 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

The maximum kinetic energy of the ejected electrons is given by:
KEmax = hν - φ
where h is Planck's constant, ν is the frequency of the photons, and φ is the work function of the metal.

We can convert the wavelength of the photons to frequency using the equation:
ν = c/λ
where c is the speed of light.

Substituting the given values, we get:
ν = 3.00 × 10^8 m/s / (240 × 10^-9 m) = 1.25 × 10^15 Hz

Next, we can rearrange the first equation to solve for the work function:
φ = hν - KEmax

Substituting the given values, we get:
φ = (6.626 × 10^-34 J ∙ s) × (1.25 × 10^15 Hz) - (11 × 1.60 × 10^-19 J)
φ = 3.73 eV

Therefore, the answer is A) 3.73 eV.

Photoelectric Effect: Upon Being Struck by 240-Nm Photons, a Metal