CEM 141
CEM 141 MSU Exam 2 Study Questions with
Answers Graded A+ 2026
Lights acts as what? -Correct Answer ✔-Particle and wave.
Wavelength -Correct Answer ✔-The distance (m) of waves from peak to peak.
Short: x-ray (red), long: infrared (blue)
Short - higher energy
Long - lower energy
Frequency (V) -Correct Answer ✔-The number of wavefronts per second. Highest:
x-ray
Velocity of Light -Correct Answer ✔-C = 3.00 X 10^8
= wavelength X frequency
Amplitude -Correct Answer ✔-The intensity, height of peaks of waves. Highest:
blue light
Energy of Wave (J) -Correct Answer ✔-Increases as frequency increases and as
wavelength decreases. Highest: x-ray
Range of Wavelengths -Correct Answer ✔-10^-16 - 10^8 = 24. Only a third are
visible
Black Body Radiation -Correct Answer ✔-When a mass is heated it emits a type of
EM radiation, at very high temps the mass becomes "white hot" because all
wavelengths of visible light become equally intense
Photoelectric Effect -Correct Answer ✔-Metals emit electrons when
electromagnetic radiation shines on the surface, light is transfers energy to the
electrons at the metal's surface where it's transformed into KE that gives the
electrons enough energy to leave the atom
CEM 141
, CEM 141
Depends on frequency not intensity
How many electrons are emitted if the light is below it's threshold frequency no
matter the intensity? -Correct Answer ✔-None.
What increases the number of electrons to be emitted by the photoelectric
effect? -Correct Answer ✔-Intensity.
A particle that transfers light energy with a definable energy, emits one electron
energy of = h (6.626 x 10^-34 J) -Correct Answer ✔-Photon.
Energy of light equation? -Correct Answer ✔-E = hV.
h -Correct Answer ✔-Planck's constant, the energy of a photon.
What happens to the energy when there is a short wavelength? -Correct Answer
✔-High energy.
Light from the sun (white light) can be separated by a prism to create this, only a
small part of the full EM spectrum? -Correct Answer ✔-Visible Spectrum.
Atomic Emission Spectrum -Correct Answer ✔-Spectrum that emits photons,
energy diagram: electron goes down energy levels.
Atomic Absorption Spectrum -Correct Answer ✔-Spectrum that absorbs photons,
energy diagram: electrons goes up in energy levels.
Heisenberg Uncertainty Principle -Correct Answer ✔-Principle states that we can't
accurately measure both the position and the energy of a small particle (electron)
Bohr's model did - why its wrong.
Schrodinger's Wave Equation -Correct Answer ✔-Treated electron as waves
derived by mathematical descriptions of energies.
Psi = wave function of an electron
CEM 141
CEM 141 MSU Exam 2 Study Questions with
Answers Graded A+ 2026
Lights acts as what? -Correct Answer ✔-Particle and wave.
Wavelength -Correct Answer ✔-The distance (m) of waves from peak to peak.
Short: x-ray (red), long: infrared (blue)
Short - higher energy
Long - lower energy
Frequency (V) -Correct Answer ✔-The number of wavefronts per second. Highest:
x-ray
Velocity of Light -Correct Answer ✔-C = 3.00 X 10^8
= wavelength X frequency
Amplitude -Correct Answer ✔-The intensity, height of peaks of waves. Highest:
blue light
Energy of Wave (J) -Correct Answer ✔-Increases as frequency increases and as
wavelength decreases. Highest: x-ray
Range of Wavelengths -Correct Answer ✔-10^-16 - 10^8 = 24. Only a third are
visible
Black Body Radiation -Correct Answer ✔-When a mass is heated it emits a type of
EM radiation, at very high temps the mass becomes "white hot" because all
wavelengths of visible light become equally intense
Photoelectric Effect -Correct Answer ✔-Metals emit electrons when
electromagnetic radiation shines on the surface, light is transfers energy to the
electrons at the metal's surface where it's transformed into KE that gives the
electrons enough energy to leave the atom
CEM 141
, CEM 141
Depends on frequency not intensity
How many electrons are emitted if the light is below it's threshold frequency no
matter the intensity? -Correct Answer ✔-None.
What increases the number of electrons to be emitted by the photoelectric
effect? -Correct Answer ✔-Intensity.
A particle that transfers light energy with a definable energy, emits one electron
energy of = h (6.626 x 10^-34 J) -Correct Answer ✔-Photon.
Energy of light equation? -Correct Answer ✔-E = hV.
h -Correct Answer ✔-Planck's constant, the energy of a photon.
What happens to the energy when there is a short wavelength? -Correct Answer
✔-High energy.
Light from the sun (white light) can be separated by a prism to create this, only a
small part of the full EM spectrum? -Correct Answer ✔-Visible Spectrum.
Atomic Emission Spectrum -Correct Answer ✔-Spectrum that emits photons,
energy diagram: electron goes down energy levels.
Atomic Absorption Spectrum -Correct Answer ✔-Spectrum that absorbs photons,
energy diagram: electrons goes up in energy levels.
Heisenberg Uncertainty Principle -Correct Answer ✔-Principle states that we can't
accurately measure both the position and the energy of a small particle (electron)
Bohr's model did - why its wrong.
Schrodinger's Wave Equation -Correct Answer ✔-Treated electron as waves
derived by mathematical descriptions of energies.
Psi = wave function of an electron
CEM 141
