In a photoelectric effect experiment, electrons emerge from a copper surface with a maximum kinetic energy of 1.10 eV when light shines on the surface. The work function of copper is 4.65 eV. Which one of the following values is closest to the wavelength of the light? (h = 6.626 × 10^-34 J ∙ s, c = 3.00 × 10⁸ m/s, 1 eV = 1.60 × 10^-19 J) A) 220 nm B) 150 nm C) 360 nm D) 1100 nm

Question

Quizplus · Accepted Answer

We can use the formula for the photoelectric effect:

Kinetic energy of electron = Energy of photon - Work function

We are given the maximum kinetic energy of the electrons and the work function of copper:

1.10 eV = Energy of photon - 4.65 eV

Solving for the energy of the photon:

Energy of photon = 5.75 eV

We can convert this energy to wavelength using the formula:

Energy of photon = hc/λ

where h is Planck's constant and c is the speed of light. Rearranging the formula:

λ = hc/Energy of photon

Plugging in the values and converting electron volt to joules:

λ = (6.626 × 10^-34 J∙s) × (3.00 × 10^8 m/s) / (5.75 × 1.60 × 10^-19 J)

λ = 220 nm

So the closest choice is A) 220 nm.

In a Photoelectric Effect Experiment, Electrons Emerge from a Copper