D2L-Exp6
docx
keyboard_arrow_up
School
Broward College *
*We aren’t endorsed by this school
Course
2054
Subject
Law
Date
Apr 3, 2024
Type
docx
Pages
7
Uploaded by samisharkey
Ohm’s Law
Professor Dhiraj Maheswari
February 26
th
, 2024
Purpose
The purpose of this experiment is to use a simulation to investigate the relationship between current, voltage, and resistance. In the experiment, determine the direction of the electron flow
and define positive and negative terminals of a battery and the resistance based on current and voltage measurements. Introduction
Ohm’s law states that the voltage across a conductor is directly proportional to the current flowing through it, provided all other physical conditions remain constant. The equation for the formula is E = I x R, or voltage = current x resistance, where resistance (R) is reported in ohms (
). The only way you can measure the resistance in a powered circuit is if you can measure the voltage and the current through
Procedures
1.
Open the simulation using the link to PhET Interactive Simulations at the University of Colorado Boulder: PhET Interactive Simulations
2.
Explore the options available in the simulator for Ohm’s law (see screenshot below).
3.
Use the sliders for voltage and resistance and observe what happens with the current.
Note the keyboard symbol at the bottom right corner for smaller steps adjustments.
Data and Evaluation collection:
1.
Complete the tables for the 3 fixed resistances.
2.
Using the sliders on the right side in the simulator adjust the value for the first given resistance of 850 ohms. 3.
Keep that resistance the same as you are changing the voltage and record the current flowing.
4.
Record the measured current in the table, corresponding to the resistance.
5.
Repeat steps 2-4 for the other two resistances and fill in the tables.
R = 850
R=470
R = 120
Graphing, Data Analysis:
1. Using the Vernier Graphical Analysis tool, plot the graphs Voltage vs. Current, and find the slope for each graph. Insert your graphs into the lab report.
Voltage
(V)
Current
(A)
1
1.0
.0012
2
1.5
.0018
3
2.5
.0029
4
3.5
.0041
5
4.0
.0047
6
5.0
.0059
7
6.0
.0071
8
7.5
.0088
9
8.5
.0100
10
9.0
.0106
Voltage
(V)
Current
(A)
1
1.0
.0021
2
1.5
.0032
3
2.5
.0053
4
3.5
.0074
5
4.0
.0085
6
5.0
.0106
7
6.0
.0127
8
7.5
.0161
9
8.5
.0180
10
9.0
.0191
Voltage
(V)
Current
(A)
1
1.0
.0083
2
1.5
.0124
3
2.5
.0207
4
3.5
.0289
5
4.0
.0331
6
5.0
.0413
7
6.0
.0496
8
7.5
.0620
9
8.5
.0702
10
9.0
.0744
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help
R=850 Ω graph:
m=850.4
R=470 Ω graph:
m=470
R=120 Ω graph:
m=121.1
2. What kind of relationship did you obtain?
Based on the graphs, the relationship between current and voltage is linear. 3. Calculate the % error for the 3 resistors (slope – experimental value; given resistance – accepted value). Include your calculations.
| 850.4-850 | x 100 = .047%
850
| 470-470 | x 100 = 0.00%
470
| 121.1 – 120 |
x 100 = .92%
120
Results and Conclusion
From the graphs, it can be concluded that voltage and current have a linear relationship. Because resistance cannot be measured, Ohm’s law allows it to be calculated if current and voltage are known. It is now known that the current flowing through the conductor is directly and linearly proportional to the voltage. Percent error was less than 1% in all three trials.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help