Resistor Circuits Lab: How do conservation lows apply to a simple series or parallel resistor circuit? Central Challenge In this investigation, students explore simple series and parallel resistor circuits with a voltmeter and ammeter and encounter Kirchhoff's rules through inquiry. Objectives After completing this investigation, you should be able to: Connect several bulbs in various series and parallel combinations; Use a voltmeter to measure potential difference; Use an ammeter to measure current; Describe and apply the relationships among the potential differences around a closed loop in a circuit; Explain how conservation of energy is related to the potential differences in a circuit; Articulate and apply the relationship between the currents entering any point in a circuit and the currents leaving that same point; and Explain how conservation of charge is related to the current flow in a circuit. Background Of all the conservation laws, the conservation of energy is the most pervasive across all areas of physics and the sciences. Conservation of energy occurs in all physical, chemical, biological, and environmental processes. In circuits, charges gain energy in the battery and then that energy is dissipated in ohmic resistors as thermal energy, and in bulbs as thermal energy and light. Kirchhoff's loop rule states that the energy gained from the battery is equal to the energy loss in the circuit. In particular, potential differences across resistors in series are added together or combined, and the total is equal to the battery potential difference. Potential differences across resistors in parallel are equal to each other. Conservation of electric charge is another fundamental conservation principle in physics. All processes in nature conserve electric charge. The total electric charge after an interaction or any other type of process always equals the total charge before the interaction or process. A common example is found in electric circuits, in which charge (typically electrons) moves within a circuit. Applying conservation of charge to a single point in the circuit, or through a cross-section of any wire in the circuit leads to Kirchhoff's junction rule. The sum of the currents flowing into any point in the circuit is the same as the sum of the currents flowing out of that point, since charge is neither created nor destroyed. This leads to the rules that govern current in simple series and parallel circuits. The currents are the same for two resistors in series, and the currents for two resistors in parallel with a battery add up to the total current through the battery. These initial investigations in basic circuit behavior are the foundations for further studies in physics, electrical engineering, and general engineering. Such circuits are used as models for body systems in medical school as well. Proper understanding of basic circuit theory will support students in the more challenging aspects of circuits such as advanced circuits (multiple loops and multiple potential sources) and RC circuits.Equipment and Materials 4-cell battery holder Three D-cell batteries 3-4 #1 14 round bulbs Connecting wires (inexpensive alligator clip leads work well) Basic multimeters or student single-value meters (voltmeter and ammeter) Extra fuses for the ammeters (Optional) Basic single pole throw switch Procedures Determine the relationship between potential differences across resistors and batter in several circuits, including the following: Two bulbs in series with each other and a battery Two bulbs in parallel with each other and a battery Three bulbs in a series-parallel combination, both one bulb in series with a parallel combination (see Figure 1) and one bulb in parallel with a series combination (see Figure 2) Figure 1 Figure 2 Also, in each case, use the same kind of bulb in each of the above scenarios, and also with different types of bulbs on the same circuit. Then, use both types of bulbs in more complicated three-bulb circles or even four-bulb circuits to test any theories that you come up with during your exploration. In the second part of the investigation, use a multimeter connected as an ammeter and explore the relationships among the currents at various points in the circuit. Analyzing Results In your report, answer the following questions. What can you conclude about how potential differences are related for several resistors in series with a battery?' What can you conclude about how potential differences are related for several resistors in parallel with a battery?' How might these conclusions be interpreted from a conservation of energy perspective? What can you conclude about how currents are related for several resistors in series with a battery? What can you conclude about how currents are related for several resistors in parallel with a battery? How might these conclusions be interpreted from a conservation of charge perspective?Resistor Circuits Lab: How do conservation lows apply to a simple series or parowel resistor circuit? Can you extrapolate these conclusions to more complex circuits with resistors in series and parallel combinations Report Once you have your plan, conducted your plan and collected data, and analyzed the results, you are ready to report your results to your teacher. In your report, you need to indude the following: An explanation of the purpose of each part of the lab An explanation of the procedures used for each part of the lab Raw data and representations thereof (ion. graphs, data chants, etc) for each part of the lab A discussion of the results of the laboratory that addresses the purpose of each part of the lab Make sure to address each aspect of rubric, as wall Rubric You will be ascraved using the following rubric. 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