Pre-Lab 7 Assignment: Capacitors and RC Circuits

Capacitors and RC Circuits v 0.3Step 3: Next, move the switch back to position 2. Describe, in detail, what happens to thebrightness of the bulb. Note that this removes the battery from the circuit, but completesa circuit that contains just the capacitor and the light bulb. Did the bulb light againwithout the battery in the circuit? If so, where did the bulb get the electrical energyfrom?Question 3.3 Draw a qualitative sketch on the axes below of the approximate brightnessof the bulb as a function of time when it is connected to the capacitor without the battery,i.e., when the switch has been moved to position 2. Start with t = 0 as the time when theswitch was moved to position 2.BrightnessTimeQuestion 3.4 Explain why the bulb behaves in this fashion. Is there a charge on thecapacitor after the switch is in position 1 for a little while? What happens to this chargewhen the switch is moved back to position 2?Step 4: Openthe experiment file called Capacitor Decay(L7A3-1), anddisplay the axes shownon the next page.Step 5: Connect the current probe and the voltage probe to the interface, and zero the probeswith nothing attached to them.Step 6: Connect the current and voltage probes as shown in Fig. 6 so that the current probemeasures the current through the light bulb and the voltage probe measures the potentialdifference across the capacitor.Step 7: Next, move the switch to position 2. Begin taking the data. When the graph linesappear on the screen, move the switch to position 1. When the current and voltage datastop changing with time, move the switch back to position 2.PHYS-204:Physics II Laboratory 12