Your name: _____________________

Please print this page, fill it in, and show it to your TF at the start of your lab session.

The photoelectric effect describes the phenomenon of electrons being emitted from a surface when light shines on the surface. To prepare yourself for the experiment you should review the following concepts.

The electron-volt (eV) is a unit of energy. How do you convert from electron-volts to joules?

The apparatus you will use includes a diffraction grating, which you should be familiar with from PY212 or PY252. Click the "Simulation 1" button below and use the simulation to answer the following question.

Which simulation correctly shows what a diffraction grating will do to a beam of light consisting of a combination of a particular wavelength of red light, a particular wavelength of blue light, and a particular wavelength of green light? Note that simulation 1 shows only the first-order spectrum.

The correct option is:

Option 1

Option 2

Option 3

Briefly justify your answer:

Now click the "Simulation 2" button below and use the simulation to answer the following question.

Which option correctly shows all the orders in the spectrum? The diffraction grating has a grating spacing of 2000 nm, while the three wavelengths of light in the beam are 450 nm, 550 nm, and 650 nm. Note that the different options differ only in the outer 1 or 2 lines.

The correct option is:

Option 1

Option 2

Option 3

Option 4

Briefly justify your answer:

In the experiment you should be able to determine a value of Planck's constant, h. What is the accepted value of Planck's constant? State it in units of J s as well as eV s.