Physics 132 LabLab #5 DC CircuitsExperimental Design and Modeling● Connect the red wire from the PASCO 550 power supply to the red post of the 100 ohmresistor. Connect the black wire from the PASCO 550 power supply to the black post of the 100 ohmresistor. now you have a circuit. The power supply measures the amount of current through the circuit.● Connect the red and black wires from channel A of the PASCO 550 to the red and black postsof the 100 ohm resistor respectively. Channel A will measure the voltage applied across the resistor.● Use the PASCO Capstone software to measure the voltage and current for the resistor.1. Record about 10 measurements of voltage and current for the the resistor. Your measurementsshould range from -5V to 5V. Record measurements in spreadsheet provided.Resistor 1Current (A)Voltage (V)-0.05168-4.975-0.04133-3.979-0.03097-2.984-0.02064-1.989-0.01028-0.9930.010420.9970.020771.9910.031112.9860.041463.9820.051824.976Now that you have taken a set of measurements of voltage and current for the resistor let’s try to figuresomething about the resistor. Is there a pattern between the voltage across and current through aresistor? How can we understand what the pattern is?The pattern is that as voltage increases, so does the current. This means the two have a directrelationship. We can understand what the pattern is by graphing the values we recorded andseeing their relationship.2. Make a graph of voltage vs. current for the resistor. Make sure the voltage is plotted on they-axis (vertical) and current is plotted on the x-axis (horizontal).3. Describe the relationship between voltage and current for the resistor. Explain a mathematicalmodel for the relationship. What are the parameters in the model you would use and how do theparameters relate to properties of the resistor?For the resistor, there is a positive linear relationship between the current and voltage. Thismeans that as the current increases, the voltage also increases. The parameters are slope= 96.1and y-intercept= -0.00534. In relationship to the resistor, the slope is equivalent to the resistanceof the resistor in ohms. The y-intercept would be equal to the voltage when current is equal tozero.● Now connect the red and black wires from channel A to the red and black post of the secondresistor.4. Record about 10 measurements of voltage and current for the second resistor. Yourmeasurements should range from -5V to 5V. Record measurements in spreadsheet provided.Resistor 2Current (A)Voltage (V)-0.05159-4.975-0.04128-3.979-0.03093-2.984-0.02062-1.989-0.01027-0.9930.010420.9960.020761.9910.031072.9860.041413.9820.051754.9765. Make a graph of voltage vs. current for the second resistor. Make sure the voltage is plotted onthe y-axis (vertical) and current is plotted on the x-axis (horizontal).6. Describe the relationship between voltage and current for the second resistor. Explain amathematical model for the relationship. What are the parameters in the model you would use and howdo the parameters relate to properties of the second resistors?There is a positive linear relationship between the current and the voltage for the second resistor,so as the voltage increases, so does the current. The mathematical relationship between voltageand current can be seen in the formula V=RI, where V = voltage, R = proportionality constant,and I = current. In the model we used, the parameters are slope= 96.3 and y-intercept = -0.00583.The slope is equivalent to the resistance of the resistor measured in ohms, the y-intercept isequivalent to the voltage when the current is 0.Series and Parallel CircuitsOne device in a circuit is not very interesting or useful. Let’s consider what happens when more than ondevice is connected in a circuit. Devices can be connected two ways: in series and in parallel. Firstconnect the two 100 ohm resistors in series (shown below).● The red wire from the power supply is connected to the red post of the first resistor.● The black wire from the power supply is connected to the black post of the second resistor.● Connect a red wire from the black post of the first resistor to the red post of the second resistor.You now have a series circuit. The red wire between the two resistors means there is only one pathbetween the resistors that current can flow. That means the current through one resistor will always bethe same as the current through the other. Let’s see what happens as we varies the voltage across theseries circuit● Connect the red wire from channel A to the red post of the first resistor and connect the blackwire from channel A to the black post of the second resistor.7. Record about 10 measurements of voltage and current for the two series resistors. Yourmeasurements should range from -5V to 5V. Record measurements in spreadsheet provided.SeriesCircuitResistor 1and 2Current (A)Voltage (V)-0.02599-4.978-0.02081-3.982-0.01559-2.986-0.01037-1.99-0.00516-0.9940.005240.9970.010481.9930.015662.9880.020893.9850.026124.988. Make a graph of voltage vs. current for the two series resistors. Make sure the voltage is plottedon the y-axis (vertical) and current is plotted on the x-axis (horizontal).9. Describe the relationship between voltage and current for the two series resistors. Explain amathematical model for the relationship. What are the parameters in the model you would use and howdo the parameters relate to properties of the two resistors?This two series resistor model shows a positive correlation between current and voltage. Thismathematical relationship can be explained by the formula V=RI, where V = voltage, R =proportionality constant, and I = current. In the model we used, the parameters are slope= 191and y-intercept = -0.00768. The slope is equivalent to the resistance of the resistor measured inohms, the y-intercept is equivalent to the voltage when the current is 0.Another way to connect two resistors is in parallel. This is
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