Activity 4: Energy Stored in a Parallel Plate Capacitor 24. Select a separation distance and a plate area. Once you made such a selection, the capacitor has a fixed capacitance. List the corresponding values below: d = A = C = 25. Without changing the separation distance d and the plate area A, use the battery slider to change the potential difference between the plates and the charge on the top plate of the capacitor. Record the values in Table 4. Repeat the procedure to have at least seven sets of values. Table 4 Capacitor Top Plate Stored 1 . CV2 102 NIH Voltage, V NIH Charge, Q Energy, U 2 C (V) (10-12 C) (J) (J) (J) (J) Do your Table 4 values confirm that the total stored energy U can be calculated as U = = CV2 = = QV = ? References: CC-BY license, PhET Interactive Simulations, University of Colorado Boulder, http://phet.colorado.eduPHY 242 Laboratory LABORATORY 5: CAPACITORS Objectives: I Determine the relationship between charge and voltage for a capacitor. ('KK HES I Explore the effect of plate separation and plate area on the capacitance . ' lal of a parallel plate capacitor in a circuit. I Determine the relationship between the energy stored in a capacitor and the charge on the plates and the voltage for capacitor. Materials Required: Computer with Excel and access to simulation I Capacitor Lab Basics: https://phet.colorado.edu/enfsimulationfcapacitor-lab-basics Software Requirements: Windows Macintosh Chromebook Linux iPad Mobile Phone Chrome. Edge Chrome. Safari Chrome Not recommended Safari Not recommended Introduction: A capacitor is an electronic component that stores electrical energy in an electric field. Most capacitors contain two electrical conductors separated by a nonconducting dielectric medium (glass, ceramic, plastic fihn, paper, mica. and oxide layers) acting to increase the capacitor's charge capacity. When two conductors experience a potential difference, an electric eld develops across the dielectric, causing a net positive charge to collect on one plate and net negative charge to collect on the other plate. Capacitance is defined as the ratio of the electric charge on each conductor to the potential difference between them C = g The unit of capacitance in the SI is the farad (F = 1 C/V). A parallel plate capacitor, the simplest model capacitor, consists of two conducting plates. each of area A, separated by a gap of thickness :17 containing a dielectric. It is assumed the gap is much smaller than the dimensions of the plates. The capacitance of a capacitor is proportional to the surface area of the plates (conductors) and inversely related to the gap between them C = 5%4. To increase the charge and voltage on a capacitor, work must be done by an external power source to move charge from the negative to the positive plate against the Cnnductive Plates opposing force of the electric eld. The work required to move the charge is stored as energy in A in! the increased electric eld between the plates. The total stored energy U can be calculated as: T 1 1 1 2 U = ECVZ = E QV = EQ?. Dielectric 111 a simple parallel-plate capacitor, a voltage applied between the two conductive plates creates a uniform electric eld between those plates. The electric eld strength in a capacitor is directly proportional to the voltage applied and inversely proportional to the distance between the plates: E = g. Since the electric eld strength must not exceed the breakdown eld strength of the capacitor. there is a maximum rated voltage for any capacitor, If the breakdown voltage is exceeded, an electrical arc is generated between the plates. and can destroy the capacitor instantly. Activity 1: Relationship between the Charge on the Plates and Voltage 1. Start the Capacitor Lab Basics m1", simulation and explore it. Choose the Capacitance tab. Make sure that the Plate Charges, Bar Graph (Capacitance, Top Plate Charge, and Stored Energy), and Electric Field boxes are checked, '..\".... W i: TOGGLE Switch La\" __ ADJUST plate to dusconneci \" g # separation and '_. __ ' battery , pale area 7 if A VIEW electric field \"\"95 SET voltage ' across canoe-tor {when connected) J MEASURE the voltage 2. Select a separation distance d. and a plate area A. Once you made such a selection. the capacitor has a xed capacitance C. List the corresponding values below: d = 6.0 mm A 26.0 mm C 20.30 pF 3. Connect the battery to the plates of the capacitor. Use the battery slider to increase the battery potential difference (voltage) Vbarrery to the maximum value (1.5 V) 4. Connect one of the voltmeter's leads to the top plate, and the other lead to the bottom plate, to measure the difference in potential V between the plates. Use the Top Plate Charge on the Bar Graph meter to read the charge Q on the top plate of the capacitor. Record them in Table 1 below. 5. Without changing the separation distance d and the plate area A, use the battery slider to change the potential difference between the plates and he charge on the top plate of the capacitor. Record the values in Table 1. Repeat the procedure to have at least ve sets of values. Table 1 Battery Voltage, Vining\