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Data Analysis -- Charging and Discharging a Capacitor

Each group must include a copy of your graphs.

  1. Calculate a theoretical value for the charging half-life. Show all work.
  2. Calculate a theoretical value for the discharging half-life. Show all work.
  3. Using the experimental value for the charging half-life, calculate an experimental value for the capacitance.
  4. Using the experimental value for the discharging half-life, calculate an experimental value for the capacitance.

Questions -- Charging and Discharging a Capacitor

  1. Calculate a percentage difference between the theoretical and the experimental value for the charging half-life. Repeat for the discharging half-life. Show all work.
  2. Calculate a percentage difference between the theoretical and the experimental value for the capacitance. Do for both procedures, charging and discharging. Show all work.
  3. The industry standard for capacitance allows a 20% difference between the theoretical and the experimental values for the capacitance. Is your percentage difference within this range? What are two factors that could account for this percentage difference? Answer for both the charging and the discharging procedures.
  4. Why does the area under the curve for the current vs time graph represent the charge stored in the capacitor? Use dimensional analysis to support your answer.
  5. Knowing the charge stored on the capacitor and the maximum voltage, calculate the energy stored in the capacitor. Do this for the charging and the discharging procedures. Show all work. (This will be a theoretical value for the energy.)
  6. Calculate a value for the energy stored in the capacitor, knowing your experimental value for the capacitance and the maximum voltage. Do this for the charging and the discharging procedures. Show all work. (This will be an experimental value for the energy.)
  7. Compare the answers to five and six using a percentage error calculation. Do this for the charging and the discharging procedures. Show all work.
  8. Why did voltage start at a minimum and reach a maximum as the capacitor charged? In your answer, define voltage. Relate the definition of voltage to the process of charging a capacitor.
  9. Why did current start at a maximum and reach a minimum as the capacitor charged? In your answer, define current. Relate the definition of current to the process of charging a capacitor.