PHY 184 General Physics Laboratory II Lab 8: Capacitors Virtual Lab Students' Names: Section: Objective of lab To understand and study the properties of a capacitor. Activity 1: Solve the following problem For the system of capacitors shown in the figure below, find (a) the equivalent capacitance of the system, (b) the charge on each capacitor, and (c) the potential difference across each capacitor. You must show all work! 3.00 /F 6:00 MF 2.00 UF 4.00 UF 90.0 Vcapacitance in the space provided below. Capacitance' 0.89 x 10^-13 2. Write down the top plate charge for the different voltage values given in table 1. 3. Voltage (V) Top Plate Charge (C) Top Plate Charge (PC) 0 OC O PC, 0.5 0.44 x 104-13 C 0.044 PC 1.0 0.88 x 10^-13 0.088 PC 1.5 1.33 x 10^-13 0.133pC Table 1 2 4. Once you have completed the table, graph charge on the y- axis and the voltage on the x-axis. S. Include an equation on the graph and R2 value. 6. Once you have the equation, find the value of the capacitance from your graph. Describe your method. 7. Use the measured value of the capacitance and the calculated value to find the percent error. Describe your method Task 2: Graph of Capacitance vs. Plate Arca 1. Reset the simulation. 2. Set the plate separation to 10 mm. 3. Record the capacitance for each of the area settings you see in table 2 below. (Move the plate arrow to control the area settings in the simulation.) Plate Area (mm Capacitance (F) Capacitance (PF) 0 OF O PF 100 0.89 x 10^-13 F 0.089 PF 150 1.33 x 10^-13 F 0.133 pF 200 1.77 x 10^-13 F 0.177 pF 250 2.23 x 10^-13 F 0.223 PF 300 2.66 x 10^-13 F 0.266 PF 350 3.09 x 10^-13 F 0.309 pF 400 3.54 x 10^-13 F 0.354 pF Table 2 4. In Excel, Graph the Capacitance on the y-axis versus the Area on the x axis. 5. Include an equation and R2 value on your graph. 8, Once you have the equation find the, plate separation from your graph. Describe your method. 9, Use the measured value of the plate separation and the calculated value to find the percent error. Describe your method. sibility; InvestigateTask 3: Graphs of Capacitance vs. Separation Distance (d) and Capacitance vs. 1/d. 1. Reset the simulation. 2. Set the plate area to 100 mm? 3. Record the capacitance for each of the separation settings in the table below. (You can change the values for d by moving the arrows.) Separation (mm) 1/separation (mm ) Capacitance (F) Capacitance (PF) 5.0 1/5.0=0.2 1.77 x 10^-13 F 0.177 pF 6.0 1/6.0=0.17 1.46 x 10^-13 F 0.146 pF 7.0 1/7.0=0.14 1.27 x 10^-13 F 0.127 pF 8.0 1/8.0=0.13 1.10 x 10^-13 F 0.110 pF 9.0 1/9.0=0.11 0.99 x 10^-13 F 0.099 pF 10.0 1/10.0= 0.1 0.89 x 10^-13 F 0.089 PF 4. In Excel, graph the Capacitance on the y-axis versus the plate separation on the x-axis. You do not need to put an equation or R2 value on this graph. 5. You will need to linearize this graph. To do this, make a second graph in Excel with the Capacitance on the y-axis and 1/d on the x-axis. 6. Include an equation and R2 value on your graph. 10. Once you have the equation find the, plate area from your graph. Describe your method. 11. Use the measured value of the plate area and the calculated value to find the percent error. Describe your method. Activity 3: Capacitors in series and parallel. 1. Click on Multiple Capacitors. 2. On section View, check the boxes: Plates Charges, Electric Field Lines, and Capacitance. 3. Select "3 in series". For Capacitance of 1.00 x 10-13 E, for the 3 capacitors: What is the magnitude of the total Capacitance? a. 0.03 x 10^-12 F 5. For Capacitance of 1.00 x 10-13 F, for the 3 capacitors: Is the total Capacitance greater than or lower than the Capacitance of each of the capacitors connected in series? a. The Capacitance is lower than the Capacitance of each of the capacitors connected in series.8. For Capacitance of 1.00 x 10" F, for the 3 capacitors: 1 lower than the Capacitance of each of the capacitors connected in parallel? a. The Capacitance is greater than the Capacitance of each of the capacitators connected in parallel. Activity 4: Dielectric in a Capacitor. 1. Click on Dielectric. 2. On section View, check the boxes: Plates Charges, Electric Field Lines, Capacitance, Plate Charge and Stored Energy. 3. Increase the voltage of the battery from 0 to 1.5V, maintain the plate area in 100.0 mm? and the separation between plates in 5.0 mm. 4. Select Teflon as dielectric and move the dielectric, slowly, toward the Capacitor such that will be completely in between the plates of the capacitor (offset of 0.0 mm). 5. How changed (increased or decreased) the Capacitance, the Plate Charge, and the Stored Energy as you moved the dielectric toward the Capacitor? a. The Capacitance, Plate Change, and Stored energy all increased. 6. For a constant value of plate area equal to 100 mm?, start increasing the distance between plates, and record the magnitude of capacitance with the increase of the distance between plates. Record your results on table 5 below. Plate Area equal to 100 mm?, voltage of 1.5 V, dielectric Teflon. Plate Separation (mm) Capacitance (F) 5.0 3.72 x 10^-13 F 6.0 3.06 x 10^-13 F 7.0 2.66 x 10^-13 F 8.0 2.30 x10^-13 F 9.0 2.07 x 10^-13 F 10.0 1.86 x 10^-13 F Table 5 7. Using Microsoft Excel, construct a graph of Separation between plates (x-axis) vs. Capacitance (y-axis). Add the trendline that better fits the data points and show the equation of the trendline. What does the slope represent? 8. Using the slope of the trendline, determine the dielectric constant experimentally. 9. The accepted dielectric constant of Teflon is 2.1. Find the percentage of error between the accepted value of the dielectric constant of Teflon and the value found experimentally in 4.8. ility: Investigate