Download Ohm`s law report Sogi_Fuentes

Physis 102
Ohm’s Law
Lab Report
Manju Sogi & Alma Fuentes
Abstract
This experiment will verify Ohm’s Law through the use of circuits in parallel and in
series.
Equipment
Digital voltmeter
Digital ammeter
Resistors (decade boxes)
Variable D.C. power supply
Wires
Procedure
1. Choose three resistors and label them R1, R2, R3.
2. Choose a resistance that is in the same order of magnitude across each resistor and
is greater than 20 ohms.
3. Set the power supply to 6V.
4. Construct a circuit in series and measure the current and voltage across each
resistor, record observations.
5. Construct a second circuit in parallel and measure the current and voltage across
each resistor, and the positive side of the power supply and R1, record
observations.
6. Construct a third circuit having R1 in series and R2 and R3 in parallel. Measure
voltages and currents.
Data
Insert a table for data here
Analysis
Series
R1
R2
R3
Circuit 1
Ohms
20
40
60
V1
V2
V3
Volts
1.502
1.997
2.974
I1
I2
I3
Amps
0.05
0.05
0.05
theoretical
0.0526
0.0499
0.0495
Slope
0.0368
Itotal
Parallel
Ohms
20
40
60
Circuit 2
Volts
6
6
6
Slope
6.345622
Theroetical
Amps
0.27
0.15
0.1
3.703704
6.666667
10
Amps
0.3
0.15
0.1
0.49
I Total
0.3
Circuit 3
R1
R2
R3
Ohms
20
40
60
I1
I2
I3
Amps
0.12
0.07
0.05
V1
V2
V3
Volts
2.87
3.07
3.09
Slope
0.0055
0.144
0.076
0.0515
Questions
1. What can you say about the sum of the voltage drops in Circuit 1?
The voltage across each resistor changes.
2. What can you say about the sum of the current through the resistor in circuit 2?
The current across each resistor changes and the current stays the same.
3. Construct a graph for each circuit plotting every V(I) point. Look for obvious
linear relationships and calculate the slopes of these lines.
4. Construct a table, subdivided into three parts, where every experimental value
(what you measured) is compared with its theoretical value (what you calculated
with Ohm’s Law).
Conclusion
In conclusion, we found that our data didn’t exactly match as our hypothesized
answers but nonetheless our data did come close to our theoretical answers. We
learned from this lab that the voltage in a series circuit across each resistor changes
but the current stays the same. However, in a parallel circuit, the current changes in
each resistor and the voltage stays the same.
Your graphs need a better scale. Also you need to draw the best fit line and find
the slope
Grade 70/100