Prelab questions for Photoelectric Effect Phet Simulation

1. Prelab questions for Photoelectric EffectPhet Simulation Answer these questions before coming to lab. What is the formula that relate the velocity of light, it’s wave length and its frequency? What is the frequency of a beam of light with a wave length of 190nm? How is the stopping potential in the photo electric effect related to the work function of the target metal?

2. Intensity adjustment Frequency adjustment Calculating h from Photoelectric EffectPhet Simulation Under the “Phet Simulations” icon, bring up the “Photoelectric Effect” simulation (Play with simulations -> Physics -> Quantum Phenomena -> Photoelectric Effect) Youshould see something like: Stopping potential adjustment Take a moment and play around with the three adjustment sliders shown above to get a feel for how the simulation works.

3. Part 1: Determining h • The metal for the default target is sodium. Find five different stopping voltages for five different random frequencies of light and fill in table 1 below. • Plot the stopping voltages vs the frequency to determine h.

4. Part 2: Work Function • You can change the metal of the target by using the drop-down menu in the upper right hand corner. Find the cut-off frequency for the five metals and fill in table 2 below. Table 2 • Using the value of h calculated in part 1, calculate the work function, f, for these five metals.