Phy213: General Physics III Lab page 1 of 4PCC-CascadeExperiment: Parallel Plate CapacitorsOBJECTIVES- To define capacitance and to learn to measure it with a digital multimeter- To discover how the capacitance of conducting parallel plates is related to the separation distance between the plates and the surface area of the plates.- To determine the dielectric constant for air and a plastic sheetINTRODUCTIONCapacitors are widely used in electronic circuits where it is important to store charge and/or energy or to trigger a timer electrical event. For example, circuits with capacitors are designed to do such diverse things as setting a flashing rate of Christmas lights, selecting what station a radio picks up, and string electrical energy to run an electronic flash unit. Any pair of conductors that can be charged electrically so that one conductor has positive charge and the other conductor has negative charge on it is called a capacitor.The capacitance of a given capacitor is defined as the ratio of the magnitude of the charge (on either one of the conductors), q, to the voltage (potential difference), V, applied across the two conductors, thus:qC = VordqC = dVCapacitance is a measure of the amount of net or excess charge on either one of the conductors per unit potential difference. The more charge a capacitor can store at a given voltage, the larger the capacitance. A capacitor can be made up of two arbitrarily shaped blobs of metal or it can have any number of regular symmetric shapes such as one hollow sphere inside another, or a metal rod inside a hollow cylinder … The type of capacitor that is easiest to analyze is the parallel plate capacitor. We will focus exclusively on the study of the properties of parallel plate capacitors because the behavior of such capacitors can be predicted using only simple mathematical calculations and basic physical reasoning. Also, parallel plate capacitors are easy to construct.Phy213: General Physics III Lab page 2 of 4PCC-CascadeMaterials- 2 steel sheets - LoggerPro (or Graphical Analysis)- Clay - Ruler with centimeter scale- Multimeter w/ capacitance mode- Vernier caliper or micrometer- Connecting wires- clip leadsPRELIMINARY QUESTIONS1. Capacitance represents the relationship between accumulated charge induced between a set of conductors and the applied potential difference. How would you expect the capacitance for a parallel plate capacitor to change as the area of the plates is increased? Explain your answer. 2. Since capacitance represents a coupling or communication between 2 associated conductors, how would you expect the capacitance between 2 parallel conducting platesto vary as the separation between the plates is increased? Explain your answer.PROCEDURE1. Measure the length and width of the steel sheets then determine their surface area.Width: _____________Length: _____________Surface Area: _____________2. Stack the metal sheets using a small amount of clay as a spacer. The sheets should be evenly separated by 0.5 mm or less (leave enough room to slide a plastic sheet in between the plates, you want a reasonably tight fit).3. Record the plate separation distance in Table 1.4. Using the digital multimeter, measure the capacitance. Be sure the multimeter leads donot make contact with each other. Record the measured capacitance in Table 1.5. Insert a plastic sheet about a quarter of the way between the plates. Measure the surface of the sheet that resides between the plates, then record value in Table 1.6. Measure and record the capacitance in Table 1.7. Insert the plastic sheet a little farther in between the sheets and repeat step 6. 8. Repeat step 7 for a total of 5 data points.9. After you have collected all of your data, open LoggerPro or Graphical Analysis. Create agraph of Capacitance vs. Plastic Sheet Surface Area (between the plates).Phy213: General Physics III Lab page 3 of 4PCC-CascadeDATA TABLE 1 (SEPARATION DISTANCE VS. CAPACITANCE)Separation(m)Area(Plastic Sheet)Capacitance(F)10. If your graph looks like a straight line, use the Linear Fit function to obtain a best fit line and the corresponding linear regression equation (with standard deviations for the fit). Ifthe graph does not look linear, try other functional fit equations until you find the best fit.11. Cut-and-paste the graph, with the calculated curve fit, into Microsoft Word.Question: Which function best describes the relationship between capacitance and sheet area between the plates? Question: How do your results compare with your prediction (in the Preliminary Questions) based on physical reasoning?ANALYSISThe actual mathematical expression for the capacitance of a parallel plate capacitor of platearea, A, plate separation d, and dielectric constant, -, is derived in your textbook. The result isAC = deoroAC = dkewhere -------o and -o is 8.85 x 10-12 C/N.m2. {Note: - = 1 for air.}1. Do your predictions and/or observations on the variation of capacitance with plate area and separation seem to agree qualitatively with this result? Explain. 2. Using the slope value from the C vs. A graph, calculate the dielectric constant, -.Phy213: General Physics III Lab page 4 of 4PCC-Cascade3. Using the fit constant value from the C vs. d graph, calculate the dielectric constant, -.4. What is the average value for -? Calculate the % range for your - value.5. Use one set of the measured values of area, separation distance and average dielectric constant to calculate a value of C using the equation above. Show your calculations.6. How does the calculated value of C compare with your measured value? Calculate the