Lab Notebook (7)

Lab Entry 1 Entry (9/6): 1. Charging by Friction Observations: Charge: -4.137: First, the charge sensors were hooked to the cylinder. Red on the inside cylinder. Black on the outside. When the PVC rod was wiped by the pink cloth, we put the charged rod on the metal cylinder. Then, we observed the charge turned negative. Observations Trial 2 (Leather cloth): Same procedure used above except with leather cloth. Had some positive charge but very minimal . Overall, charge still stayed negative. This shows the cloth was an insulator because charge/electrons could not move freely. Observations Trial 3( Cotton Cloth): Charge (-.100). Electrons stayed on cloth which means cloth served as an insulator. The rod didn't get much charge. Model : 2. What is the sign of the charge generated on each rod Nylon and Positive 3. How does the magnitude of charge compare between the two rod/sheet combinations? The rod and regular cloth (1st trial) had the biggest magnitude for charge compared to trial 2 and trial 3 due to alot of electrons being able to transfer to the rod giving it the biggest magnitude for charge. 4. What determines whether the rod acquires a positive or negative charge? The types of cloth and rod play a part because the cloth could be an insulator and conductor. Also it depends on whether the cloth transfers electrons to the rod which results in the cloth losing/gaining electrons. 5. Does this phenomenon violate the conservation of electric charge? No because energy can be created or destroyed, it was just transferred. This correlates with the electrons transferring from the cloth to the rod making it positive/negative.

4. Electric Discharge: Observations: responds to touch and lighting is attracted to hands as it nears or touches globe.

Activity 2: Measuring Electric Potential: 6.21 V: starting voltage 1st trail : At middle:03.09 At (20,10): 6.2 At (6,1):0.33 B: Dipole Configuration: 6.22 Voltage Model:

Area of parallel plates: 30.42mm At 200pF: Capacitance= 36pF Trial 5: Area of parallel plates: 15.6mm At 200pF: Capacitance= 20pF 1. You have three variables: C , A , and d . (The dielectric you will be using is paper and will be constant for this experiment.) Which are dependent, independent, or constant variables? Explain your reasoning. C stands for capacitance. Capacitance is not constant. It depends on the area. It also depends on the distance. This would make the distance and area variable independent while the capacitance variable is dependent. During our experiment, as the area got smaller, the capacitance decreased. As the distance between the parallel plates increased, there was a decrease in capacitance. 2. What ranges of values will you explore? How many data points will you collect within that range? How many repeated trials for each value of the independent variable will you need? Justify your choice in each case. When testing the distance, we kept the area of the parallel plates fixed. We took 5 different recordings while gradually increasing the distance between the plates. While testing the area, we kept the distance between the parallel plates fixed. We also took 5 different recordings while gradually switching up the area of the parallel plates. We folded it over and over again. We wish we could have recorded more data to obtain a more accurate graph. However, we initially were recording not so accurate results. For capacitance we stayed in between 20pF to 174pF. For distance, it ranged from 5mm to 13mm. For area, it ranged from 217.5mm to 15.6mm. 3. How will you plot the data to evaluate whether the system is consistent with the model? We entered our data points into Excel to then create a scatter plot. We created a scatter plot for Area vs Capacitance and for Distance vs Capacitance. After reviewing the scatter plot, we were able to determine the relationship between distance, area, and capacitance. 4. What are your dominant sources of uncertainty? How will you characterize, quantify, and minimize those sources?

Lab Entry: 09/27/2023 Trial 1: Testing: Length, Voltage is at 11.6 and Rod is Music Wire (3.88mm), Current @ 1.155 Length 1 @ 17cm: 0.51V Length 2 @ 24cm: 7.2V Length @ 30 cm:08.9 Length @ 10cm :02.9 Length @ 6cm:01.7 Length @ 2cm: 00.5 Length @ 12cm:03.6

Trial 2: Testing Diameter, Length is at 15cm, Voltage 11.73, Current: 1.163 Dia 1 (Brass 3.18mm): 01.9 Dia 2( Stainless Steel 3.18mm) :1.55 (voltage) 17.42 and Current (1.734) Trial 1: 2.33V Dia 3( Music Wire 3.18mm): 0.44V Dia 4(Aluminum 3.18mm): 00.7V Dia 5(Brass 2.38mm): Trial 1( End of Rod): 0.31V Trial 2( Middle of Rod) :0.30V Trial 3(Begin of Rod):0.30V Avg: 0.30V Dia 6( Brass 3.97mm): Voltage @ 10.28 and Current @ 1.026 Run 1(Begin of rod @ 10cm) : 0.60 Runl 2 ( Middle of rod): 0.60

Run 3 (End of Rod): 0.60 Avg: 0.60 Dia 7(Brass 4.76mm): Run 1( Middle of Rod): 0.6V Run 2( Beginning of Rod) :0.6V Run 3 (End of Rod): 0.6V Avg: 0.60

Trial 3: Length constant (8cm), Voltage (15.62) 1.Brass Wire(3.18mm): Voltage (13.51) and Current(1.352) Run 1: 01.0V Run 2: 01.0V Run 3: 01.0V Avg: 01.0V 2. Stainless Steel Wire, Voltage (13.51) and Current (1.352) Run 1 : 09.5V Run 2: 09.7V Run 3 : 09.6V Avg: 9.6V 3.Music Wire, Voltage (13.52) and Current (1.352) (Begin) Run 1: 02.8V (Middle) Run 2: 02.8V (End) Run 3: 02.8V Avg: 2.8V 4. Aluminum, Voltage (13.52) and Current (1.352) (Begin) Run 1: 00.4V (Middle) Run 2: 00.4V (End) Run 3: 00.4V Avg: 00.4V

1. There are many variables to consider: I , Δ V , the length of the rod that you measure the voltage drop across, the diameter of the rod, and the material the rod is made from. Which variables are dependent, independent, or constant variables? Explain your reasoning. The length of the rod, the diameter of the rod, and the material that the rod is made from are independent. Those variables will not be affected, but will affect resistivity. During this lab, while testing the length, material, and diameter of the rod, we kept some variable constants. For example, when determining how the material of the rod affects resistivity, we kept the length and diameter of the rod the same. The potential difference depended on the variables that we were testing. 2. What ranges of values will you explore? How many data points will you collect within that range? How many repeated trials for each value of the independent variable will you need? Justify your choice in each case. At times, we reached points of uncertainty. During these runs, we calculated 3 separate readings and then took the average of these readings. For the majority of the runs, we were able to obtain solid recordings. When measuring the length, we recorded 7 values ranging between 2 and 30. For the material, we measured four different materials with the same length and diameter. When measuring the diameter, we kept the material the same (brass) and the length the same, and recorded measurements with 4 different diameters.

3. How will you plot the data? We are going to plot the data on an excel sheet then create 3 separate plot graphs. This will tell us the relationship between the variables and the resistivity. 4. What are your dominant sources of uncertainty? How will you characterize, quantify, and minimize those sources? The dominant sources of uncertainty are the amount of voltage, the performance/faultiness within the lab equipment, and ensuring the circuit is set up carefully. To minimize uncertainty, we can ensure that our circuit is set up correctly, test to see if the lab equipment is performing properly, and change the amount of voltage if needed. If uncertainty still occurs, we can take multiple measurements and then take the average of those measurements.

Lab Notebook: 10\11\23 Zemyer is blue Grecia is purple ● contributed to the experimental design 4/4determined the dependent and independent variables 3/4 4/4 ○ ○ determined how to measure and collect data 4/4 4/4 ○ determined how much data to collect 4/4 All, but struggled to grasp this. 4/4 ○ determined how to plot the data 4/4 4/4; took some time but i learned ○ made a prediction of the plotted data 4/4 4/4 ○ determined the source(s) of uncertai nty 4/4 I did that ○ quantified the uncertainty 2/4 2/4 ○ other: _______ ● contributed to the lab notes all the time; everyday ● set up the equipment for data collection i excelled at all of this stuff below ○ connected the circuit 2/4 ○ adjusted settings on multimeter 4/4 ○ took preliminary measurements to test the set-up 4/4 3/4 ○ other: _______ ● made hands-on measurements/adjustments: 4/4 for all ○ with the multimeter ○ with a ruler/calipers ○ other: _______ ● contributed to the lab group discussion ○ about how to test a given model 4/4 we talked about how we go about an experiment ○ about how to develop a model from your data 4/4 4/4 i gave ideas ○ about testing the model you developed 4/4 4/4 we constructed the idea and tested it ○ other: _______ ● communicated with others outside the lab group (0/4) ○ presented your group's experimental design 1/4 we havent done this ○ explained your group's approach to testing a given model we did this to the ta; not very much ○ explained your group's approach to using your data to develop a model we explained our ideas to ta and prof and received feedback

○ explained your group's approach to testing the model you developed same as above ○ other: _______

Lab 4.1: Modeling the Magnetic Field in a slinky(unfinished) ● Figured out how the sensor takes measurement of magnetic field strength We observed a positive magnetic field when we took the logger pro probe and put it right on the slinky. Then, we observed negative values when we pulled the probe away from the slinky. Therefore, we concluded that the earth must be south pole and then the slinky must be north and therefore they attract. ● Measured the magnitude and direction of Earth’s magnetic field Part 2: Trial 1: Testing length Independent Variables: ● Current constant at .347 Amps ● Number of loops:19 Run 1: Length= 14in Avg Mag Field= 0.01383mT Uncertainty:0.008 Run 2: Length= 12in Avg Mag Field = 0.01668mT Uncertainty:0.008 Run 3: Length= 10in Avg Mag Field= 0.01712 mT

Uncertainty= 0.012 Run 4: Length= 9in Avg Mag Field= 0.02572mT Uncertainty: 0.012 Run 5: Length= 8in Avg Mag Field= 0.02565mT Uncertainty: 0.012 Run 6: Length= 6in Avg Mag Field=0.0505 Uncertainty= 0.008 Run 7: Length=4in Avg Mag Field= 0.04876mT Uncertainty= 0.12 Run 8: Length= 2in Avg Mag Field= 0.055205 Uncertainty= 0.05

Trial 2: Testing Loops Independent Variables: Current: .349 Amps

Length:36 cm Run 1: # of loops: 37 Avg Mag Field: 0.002677 Uncertainty: 0.08 Run 2: # of loops: 33 Avg Mag Field: 0.004282 Uncertainty: 0.012 Run 3: # of loops: 29 Avg Mag Field: Uncertainty: Run 4: # of loops: Avg Mag Field: Uncertainty: Run 5: # of loops: Avg Mag Field:

Uncertainty:

Lab 4.2 :Modeling Electromagnetic Induction Activity 1: ● North Pole: When the nole pole of the permanent magnet was inserted and removed, the current went from negative to positive. ● South Pole: When the south pole of the permanent magnet was inserted and removed, the current went from positive to negative. ● The faster we removed and inserted the magnet, the faster the current. ● When we first insert the north pole magnet into the solenoid we notice that the galvanometer pointed towards the left (negative current) . T his means that the current is moving in the clockwise direction. When we put in the south pole the current becomes positive (right). This means that the current is moving in the counterclockwise direction. Activity 2: Magnet falling through a pipe Investigating: What happens when a permanent magnet is dropped through a copper pipe? As the magnet falls it induces a current in the copper pipe. That current creates a magnetic field that opposes the changing field of the falling magnet, so the magnet is repelled and falls more slowly. Because there was a negative difference this means that the north pole magnet was entered through the wire first. Then, there was a positive difference which means that the south magnet was entered first. Measuring: Current in the wire coils as the magnet passes through the pipe

Run 1: Mean for Current 1: -0.008700A Mean for Current 2: -5.372E-005A

Run2: Observations: There was a positive difference within the wire which means the south pole of the magnet was entered into the rod first. Mean Current 1: -0.005295A Mean Current 2: 0.0002584A

Run 3: Observations: When the magnet entered the coil the current was positive and then exited the coil and it was negative. Then the magnet traveled up the rod and entered the other coil. The current was at first positive and then when the magnet exited the coil, the current came out negative. Current mean 1:-0.0004630A Current mean 2: 0.0002822A Activity 3:Electricity Generation Electricity generation using electromagnetic induction is based on Faraday's law of electromagnetic induction, which states that a change in magnetic field within a closed loop of wire induces an electromotive force (EMF), or voltage, in that wire.To generate electricity using electromagnetic induction, you need a source of magnetic field. You can use a magnet or an electromagnet, which produces a magnetic field. Application:

Generators: Electric generators are common devices that utilize electromagnetic induction. They consist of a coil of wire that is rotated within a magnetic field. As the coil spins, it cuts through the lines of magnetic flux creating an EMF and generating electricity. Using what we observed from the lab, if we take a magnet and move it in and out of a solenoid then we can observe a current. If we move it fast enough it will produce a voltage and that will give us power to charge it to whatever we want.

Part 1: Building the RC Circuit How we built the circuit: Firstly, we took a red wire and hooked it up to the positive terminal of the emf. Then we took this wire and connected it to the switch. Then plugged the black clip into the negative terminal and clipped it to the resistor. Then we connected another black ckip to the switch and the resistor. Next, we took another switch and connected it to the capacitor. Then to measure the voltage, we connected both clips from the voltmeter to the capacitor so it could be in parallel. Then we connected the ends to some of the clips connected to the capacitor to the ammeter so that the circuit could have current flowing through it and it would all be connected. After, we used logger pro to measure t he resistance and capacitance of the circuit components being used in the circuit. We noticed that when the circuit was charged it exponentially grew. When the circuit was discharged, it started to decrease and flatline. Voltage vs Time Graph:

Current vs Time Graph: Part 2: Capacitance: 1.6 microfarads Resistance at 200 ohms: 0.9 M ohms Time constant: 1.44 Now, we are going to replace the resistor one a different resistor that appears smaller in size Resistance:0.9 Capacitance: We measured the resistance and got a very high number in the millions. This means that it would take a very long time for the circuit to discharge.