Exploring the properties of capacitors

Part A: Find the capacitance of a single capacitor

Explore the properties of a single simulated capacitor. Calculate and measure the capacitance of capacitors wired in series and parallel and other combinations.

1.Once you have the web site up on the computer and the simulation loads, make sure the “Introduction” tab is chosen.

2.Check the following boxes:

a.View:

Plate Charges

b.Meters:  Capacitance, Plate Charge, Voltmeter

3.Drag the voltmeter leads so they touch the capacitor plates.

4.Adjust the plate separation and plate area, using the appropriate sliders, to change the capacitance to some value that you would like to use.  Record the capacitance in the blank above table 1.

5.Choose 10 voltage readings between the extremes available using the slider on the battery.  Record charge on the plate (note the sign) and voltage on the voltmeter (note the sign) in the appropriate locations in table 1.

6.Reset the simulation.

1.Check the following boxes:

Meters:  Capacitance

2.Fix the separation, d, by moving the separation slider to a value of your choosing and record in space provided above Table 2.

3.Choose 10 plate area values between the extremes for this simulation by moving the area slider.  Record the areas and the capacitance, C, for each of these area settings in Table 2.

4.Once data is collected, reset the simulation.

5.Check the same boxes as in step 1 and fix and record the Plate Area, A, in the space provided above Table 3. 

6.Choose 10 separation values between the extremes for this simulation by moving the separation slider.  Record the separations and the capacitance, C, for each of these separation settings in Table 3.

7.Once data is collected, reset the simulation.

Part C: Relationship between energy and voltage

1.Check the following boxes:

Meters: Capacitance, Stored Energy, Voltmeter.

2.Adjust the plate area and separation to get a capacitance value of your choice.  Record the Capacitance, C, in the space provided above Table 4.

3.Drag the voltmeter leads so they touch the capacitor plates.

4.Move the slider on the battery to 10 positive voltage values between zero and the extreme for this simulation.  Record each voltage and the corresponding stored energy, U, for the voltage settings in table 

5.Once data is collected, reset the simulation.

Click on the “Multiple Capacitors” tab.

1.Capacitors in series

a.In the section labeled “Meters”, check the boxes “Total Capacitance”, “Stored Charge”, and “Voltmeter”, and in the section labeled “Circuits”, click the button “3 in Series”.

b.Move the voltage slide to a maximum of 1.5 V and measure the voltage across the battery with the voltmeter.   Record as Vmax in the “3 capacitors in series” data section.

c.Use the sliders beside each capacitor to change the settings to three different values, one for each capacitor, and record in the appropriate table.

d.Now measure the voltage across each capacitor and record them as V1, V2, and V3, respectively in the appropriate table.

e.Record the total capacitance and the stored charge.

2.Capacitors in parallel.

a.In the “Circuits” section, click the button “3 in Parallel”.

b.Choose the same capacitances that you used for the series configuration and record in the appropriate table.

c.Move the voltage slide to a maximum of 1.5 V and measure the voltage across the battery with the voltmeter.   Record as Vmax in the “3 capacitors in parallel” data section.

d.Now measure the voltage across each capacitor and record them as V1, V2, and V3, respectively in the appropriate table.

e.Record the total capacitance and the stored charge.

3.Capacitor combinations.

a.Click on “2 in Series + 1 in Parallel”.

b.Choose the same capacitances that you used for the series configuration and record in the appropriate table.

c.Move the voltage slide to a maximum of 1.5 V and measure the voltage across the battery with the voltmeter.   Record as Vmax in the “2 in Series + 1 in Parallel” data section.

d.Now measure the voltage across each capacitor and record them as V1, V2, and V3, respectively in the appropriate table.

e.Record the total capacitance and the stored charge.

f.Click on “2 in Parallel + 1 in Series”.

g.Choose the same capacitances that you used for the series configuration and record in the appropriate table.

h.Move the voltage slide to a maximum of 1.5 V and measure the voltage across the battery with the voltmeter.   Record as Vmax in the “2 in Parallel + 1 in Series” data section.

i.Now measure the voltage across each capacitor and record them as V1, V2, and V3, respectively in the appropriate table.

j.Record the total capacitance and the stored charge.