Lab 5 - Electric Current

pdf

School

Life Chiropractic College West *

*We aren’t endorsed by this school

Course

3120

Subject

Electrical Engineering

Date

Apr 3, 2024

Type

pdf

Pages

4

Uploaded by MajorMaskLapwing33

Report
Name ___________________________________________ Date ______________________ Class ________________________ To observe how current changes in and out of basic resistors. You’ve been using electricity your whole life, but have you ever taken time to think about what causes the electricity to flow and how it gets to you from the power plant? You might see electric lines lining streets and coming up to each house. How much electricity can that wire handle and how do power companies measure it? Ampere, current, multimeter When you click on a light, turn on a computer, or start a car there is something that provides electricity. The electricity must flow through the different devices in order for them to work. The “something” that is flowing through the wires and the devices is what we call electric current. The current is what powers your lights where the greater the current the brighter the lights. We can measure current using a multimeter, which measures current using the standard units of amperes. The SI symbol of the ampere is the letter A . The current is what we call the flow of the electrons in the wire. The amount of current entering a wire is equal to the amount of current leaving that wire. You will use a multimeter to measure the current in different circuits. 1. How do you think the current going into a resistor compares with the current flowing out of the resistor? 1. Start Virtual Physics and select Electric Current from the list of assignments. The lab will open in the Circuits laboratory. 2. The laboratory will be set up with three simple circuits made of resistors on the breadboard. You will need to connect the Function Generator to the three different circuits you will be examining. Using the oscilloscope and the multimeter you will measure the electric current at different locations on the basic circuits and then you will measure it at different locations on the more complex circuit. 3. The Function Generator is already connected to the single resistor circuit and is set to 12 V DC, but the Function Generator is turned off. The blue wire is connected to the positive side and the green wire is set on the negative side. Use these wires when it’s time to connect the other circuits. The current going into a resistor is expected to be equal to the current flowing out of the resistor, according to the principle of conservation of electric charge. Dalton Rios
Name ___________________________________________ Date ______________________ Class ________________________ 4. Turn on the Function Generator using the power button at the top. The multimeter is set to measure current in Ampere (A) and is already attached to pin 23c on the left side of the resistor. The current will flow through the multimeter and then into the circuit. Record the current in the data table below. 5. Move the leads to the other side of the resistor by dragging the red multimeter lead to pin 20c. Record the current. Current flows from the negative to the positive so Current IN means the negative side of the resistor is in and the other side is out. The negative side is the side in which it would lead back to the black or negative lead of the function generator. The positive side is the side that would lead back to the positive lead on the function generator. 1. What will happen to the current if more resistors are put in the circuit? 1. Drag a new blue wire from the top red positive row to pin 20f in the column with the set of three connected resistors at the bottom of the breadboard. It will connect the positive side to the function generator and the first resistor in the series. Put out a new green wire to connect the last resistor in the series to the negative blue row (the end of the wire will be in 5f). Double click each of the blue and green wires from the single resistor circuit to remove them from the voltage source. 2. Now measure the current going into and out of each resistor by moving the multimeter probes as before. Record all your data in the data table below. 2. How does the three resistor circuit arrangement affect the current? Resistors Current IN (A) Current OUT (A) 1 Resistors Current IN (A) Current OUT (A) 1 (150Ω) 2 (180Ω) 3 (100Ω) The three-resistor circuit arrangement affects the current by dividing it among the resistors based on their resistance values. If more resistors are added in series to a circuit, the total resistance of the circuit will increase. 0.5 0.5 4.3 3.6 6.45 4.3 3.6 6.45
Name ___________________________________________ Date ______________________ Class ________________________ 1. Disconnect the wires connecting the series circuit to the voltage source. Now drag a yellow wire to connect the resistor in the 12 th column to the positive voltage row (place it in pin 12a) and drag a new green wire from the negative voltage row to pin 3a. 2. Record the current into and out of each resistor in the data table. 3. How does the data show that the current is not lost in a resistor? 4. What is the sum of the currents coming out of the parallel circuit? 5. Compare your predictions to what actually happened. 6. How did the current compare in the parallel circuit with that of the series circuit? 7. How did the current change with the three series resistor circuit compared to the single resistor circuit? Resistors Current IN (A) Current OUT (A) 1 (1Ω) 2 (1kΩ) 3 (200Ω) 4 (500Ω) The current changes with the three-series resistor circuit compared to the single resistor circuit by dividing the total current among the three resistors, resulting in lower current values for each resistor compared to the single resistor circuit. The current in a parallel circuit is expected to be higher compared to a series circuit due to the presence of multiple paths for the current to flow. The sum of the currents coming out of the parallel circuit is equal to the total current entering the parallel circuit. The data shows that the current is not lost in a resistor because the current going into each resistor is equal to the current flowing out of it, demonstrating the conservation of electric charge. 3402 3402 3.402 3.402 1.701 1.701 6.804 6.804
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
Name ___________________________________________ Date ______________________ Class ________________________ 8. Write an analogy that could model your understanding of current. Understanding electric current is like imagining water flowing through interconnected pipes. Voltage acts as the water pressure, pushing current through the circuit, while resistance, akin to pipe size, limits the flow of current. Current itself represents the rate of flow, analogous to the quantity of water passing through the pipes. Circuits can be arranged in series, where current flows sequentially through components, or in parallel, allowing current to take multiple paths simultaneously. Just as obstacles in pipes impede water flow, loads in circuits consume energy and affect current flow. This analogy simplifies complex electrical concepts, making it easier to grasp the behavior of electric current in circuits.