1. Consider two light fields in vacuum, one at 532 nm (green), the other at 400 nm wavelength (blue). If you multiply the wavelength of each light field with the corresponding frequency, the result will be … (A) … a larger number for the green light field than for the blue (B) … a smaller number for the green light field than for the blue (C) … the same number for the green and the blue light

2. Consider two light fields in vacuum, one at 532 nm (green), the other at 400 nm wavelength (blue). If you multiply the wavelength of each light field with the corresponding frequency, the result will be … (A) … a larger number for the green light field than for the blue (B) … a smaller number for the green light field than for the blue (C) … the same number for the green and the blue light namely the speed of light: c = ·

3. Photoelectric Effect Assume that electrons are emitted from the metal surface with some kinetic energy E kin. We now apply a positive voltage U to the metal, holding the detector plate at zero voltage. Which of the following statements is correct? (A) Positive voltage accelerates the electrons towards the detector plate. We will measure a current independent of the voltage as long as it is positive. (B) The voltage has to be greater than E kin in order to measure a current. Otherwise, the kinetic energy of the electrons is too great, the electrons will leave the setup and there will be no current. (C) As long as the voltage U < E kin /e, we will measure a current. Otherwise, the positive voltage creates a force that “pulls” the electrons back into the metal surface before they can reach the detector.

4. Photoelectric Effect Assume that electrons are emitted from the metal surface with some kinetic energy E kin. We now apply a positive voltage U to the metal, holding the detector plate at zero voltage. Which of the following statements is correct? (A) Positive voltage accelerates the electrons towards the detector plate. We will measure a current independent of the voltage as long as it is positive. (B) The voltage has to be greater than E kin in order to measure a current. Otherwise, the kinetic energy of the electrons is too great, the electrons will leave the setup and there will be no current. (C) As long as the voltage U < E kin /e, we will measure a current. Otherwise, the positive voltage creates a force that “pulls” the electrons back into the metal surface before they can reach the detector.

5. Photoelectric Effect EM radiation can – under certain circumstances – knock electrons out of molecules and surfaces. Imagine a clean calcium surface under vacuum, and assume that you can somehow measure if electrons are emitted from the surface. Green light strikes the surface, and no electrons are emitted. Could electrons possibly be emitted if you (A) doubled the light intensity? (B) used red light instead of green? (C) used UV light instead of green? (D) none of the above.

6. Photoelectric Effect EM radiation can – under certain circumstances – knock electrons out of molecules and surfaces. Imagine a clean calcium surface under vacuum, and assume that you can somehow measure if electrons are emitted from the surface. Green light strikes the surface, and no electrons are emitted. Could electrons possibly be emitted if you (A) doubled the light intensity? (B) used red light instead of green? (C) used UV light instead of green? (D) none of the above.

7. Light has the properties of... (A)… waves (B)… particles (C)… both (D)... neither

8. Light has the properties of... (A)… waves (B)… particles (C)… both (D)... neither