Quiz: Photoelectric Effect
Name:____________________
***Show all of your work on this page to receive full marks!***
1. If a metal with a threshold frequency of 1.1x1015 Hz is illuminated by light with a
wavelength of 1.7x10-7m, then the maximum kinetic energy of the emitted
photoelectrons will be
a. 4.4x10-19 J
b. 7.3x10-19 J
c. 1.2x10-18 J
d. 1.5x10-18 J
Use the following information to answer the next question.
When a certain metal is struck by a photon with a frequency of 8.23x10 14
Hz, the metal emits an electron with a maximum speed of 2.45x10 5 m/s.
Numerical Response #1
The work function for this metal is ___________eV. Round and record your value to 3
significant digits.
Use the following information to answer the next question.
A student was studying the photoelectric effect. The student varied the
frequency of the incident light source and observed how the speed of the
eject electrons changed. The student then plotted the following graph.
v2
(m2/s2)
Frequency (Hz)
The value of the slope of the line of best fit is 1.4x10-3 m2/s and the value of
y-intercept is -9.7x1011m2/s2.
2. Use the graph to calculate the work function in eV.
Numerical Response #2
If the stopping potential of a photocell is 5.60V, then the maximum speed of the
photoelectrons emitted is a.bcx10d m/s. Record your values for a, b, c, and d.
Numerical Response #3
If cesium has a work function of 3.8eV, the threshold frequency of cesium is a.bx10cd
Hz. Record your values for a, b, c, and d.
3. The stopping potential of photoelectrons emitted from a surface illuminated by
light with a wavelength of 490nm was 0.710V. When the incident EMR was
replaced with EMR of a different wavelength, the stopping potential was then
1.43V.
a. What is the work function for the surface?
b. What is the wavelength of the new light?
Use the following information to answer the next question.
In a photoelectric effect experiment, a student observes how changing the intensity of
the radiation incident upon a metal affects the observed photoelectrical current. The
frequency of the incoming radiation is kept constant as a controlled variable.
4. If the radiation incident on the metal has a frequency that is below the threshold
frequency, which of the lines in the graph given above displays the observed
current as a function of intensity?
a. A
b. B
c. C
d. D