Circuit Construction Kit DC Lab 6

docx

School

Indiana University, Purdue University, Indianapolis *

*We aren’t endorsed by this school

Course

21900

Subject

Electrical Engineering

Date

Apr 3, 2024

Type

docx

Pages

Uploaded by bradyspence5

Circuit Construction Kit DC This lab uses the Circuit Construction Kit DC simulation from PhET Interactive Simulations at University of Colorado Boulder, under the CC-BY 4.0 license. https://phet.colorado.edu/sims/html/circuit-construction-kit-dc/latest/circuit-construction-kit-dc_en.html Learning Goals ● Explore basic electricity relationships. ● Explain basic electricity relationships in series and parallel circuits. ● Use an ammeter and voltmeter to take readings in circuits. ● Provide reasoning to explain the measurements and relationships in circuits. Prediction Questions Consider the pictures of each of these circuits, then answer the questions below. Series Circuit Parallel Circuit Complex Circuit Figure 1: first circuit is a series circuit , second is parallel, and third is complex(mixed) 1. From the circuits above, predict which bulb (or bulbs) will be the brightest. Why do you think that? current in series connection across each resistor will be same therefore, energy consumed by each bulb = E1 = E2 = I2Rt = (V/2R)2Rt = V2t/4R hence, brightness of bulb-1 and bulb-2 will be same. In the scenario of a parallel connection, current divides evenly since each bulb is independent, hence current in each resistor equals Ip/2 = V/R. Therefore, current in the circuit = Ip = V/(R/2) = 2V/R. Thus, every bulb's energy consumption is equal to E3 + E4 = (Ip)2Rt = V2t/R. As a result, bulb-3 and bulb-4 will have the similar brightness and will be brighter than bulb-1 and bulb-2. Brightness of bulb-3, bulb-4 and bulb-7 are same and the brightest because current through these bulbs are greater. 2. Current is the flow of charge (measured in coulombs/sec = amps) in a circuit. Describe how you think current will flow in the different types of circuits above. As is well known, an electric field is created between the bulb terminals as a result of the cell creating a potential difference across the bulb. An electric force causes the charge to flow through the bulbs as a result of this electric field. Since every bulb in a series circuit is linked in a line, the charges passing through each bulb will be the same. However, with a parallel circuit, there are two paths for charges to travel, and since every bulb is the same, there is an equal supply of resistance, resulting in an equal division of current. In addition, bulb-7 in the final circuit has a potential difference equivalent to a cell's potential difference and provides less resistance since bulbs 5 and 6 are in series and have the same current. Develop your understanding: 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page1 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )

Circuit Construction Kit DC 3. Explore the Intro screen of Circuit Construction Kit DC a. Build a circuit that shows how to make a light bulb light up. b. Figure out how to measure current and voltage. c. Insert an image of your circuit with the current and voltage measured. 4. Imagine you’re an engineer making a string of battery powered holiday lights. If a bulb burns out current cannot flow through that bulb any longer like if the wire at the bulb has been cut. Figure out how to hook up 2 light bulbs and a battery so that when one bulb burns out or is disconnected the other stays lit. a. Insert images to illustrate that your circuit works as expected. b. Explain why you think it works. The reality that one lightbulb in a parallel circuit won't affect the other lights in the circuit is an evident benefit of using parallel circuits. Because there is still a separate, independent closed channel connecting each of the other loads to the source, they are still in operation. For this reason, wiring outlets and lights uses parallel circuits. When a single light on a parallel circuit burns out, the remaining lights that are wired in parallel continue to function. 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page2 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )

Circuit Construction Kit DC 5. Imagine that you want to make sure the battery for your string of lights will last as long as possible. A battery will last longer if it powers a circuit with low current. How could you hook up a battery and 2 light bulbs so the least amount of current flows through the battery? Use the measurement tools in the simulation to check your design. a. Insert images to illustrate that your circuit works as expected. b. Explain why you think it works. This is effective because a larger overall resistance is achieved when the bulbs are arranged in series. The resistance of the battery is high, which means that less current will travel through the circuit and through the battery, extending its lifespan. We must raise the circuit resistance in order to reduce the amount of current passing through the battery. A series arrangement of the lights offers greater resilience. Develop your understanding Part 2 Instructions: Your goal in this part is to write rules to describe how patterns of current and voltage in a circuit relate to the structure of the circuit. You will need to measure current and voltage in multiple places on several different circuits. Examples: Measuring Current Measuring Voltage “Current” is the flow of charge, measured in Amps (Coulombs/s). An ammeter measures the current past a single point in the circuit. “Voltage” is a measure of the difference in electric potential between two points. The voltmeter measures this difference by placing the two leads (pronounced “leeds”) at two different points. 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page3 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )

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

Circuit Construction Kit DC The current flowing through point 1 can be written as: I 1 = 0.09 A. The voltage between points A and B can be written as V AB = 9 V. A Use the table below to record your measurements and patterns you notice. You decide where will be the most useful places to take measurements, and how many to take. 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page4 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )

Circuit Construction Kit DC 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page5 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits ) Over the course of the circuit, the current fluctuates. During the branch in circuit, there is the first change in current. As soon as the electrons cross the junction and return to the battery, the current rises. The circuit's voltage stays constant throughout. It is not the same as a series circuit in that it is not consistent across the circuit. Throughout the whole circuit, the current is constant. Between the two resistors, the voltage decreases to 4.5 volts. Because the bulbs in this circuit are wired end to end, there is only one path for current to go. Throughout the whole circuit, the current is constant. The circuit as a whole operates at the same voltage. a single, closed loop with two ends. just one way for current to flow

Circuit Construction Kit DC 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page6 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits ) The circuit consists of parallel and series branches together. Nine volts total is supplied; half of this, or 4.5 volts, is applied to each of the two series lights and the single bulb. The single bulb branch receives 0.9 of the 1.35A total current, while the other branch, which has two bulbs, receives the remaining 0.45A. This is in accordance with the relationships of the voltage and current dividers. 4 ) Complex circuit ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ ____________ Commented [4]: Draw this on paper and insert an image of your drawing.

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

Circuit Construction Kit DC Summarize your understanding: 6. Compare the patterns you see in a series circuit to the ones you see in parallel and complex circuits. Write rules about voltage and current for each type of circuit. For example, “In a series circuit, I see that the current ….., whereas in a parallel circuit I see… ”. I observe that in a series circuit, the voltage declines between resistors (bulbs) but sums equivalent to the voltage of the battery. The current flows through the circuit in the same direction throughout. The voltage is constant across the parallel circuit, while current decreases between resistors. When two resistors or bulbs are connected in series, there is less current flow, which results in a decrease in the brightness of the bulbs. 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page7 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )

Circuit Construction Kit DC Test your understanding 7. Predict from your rules above, the order of the light bulbs in these circuits from brightest to dimmest. Some bulbs might be the same brightness. a) (order the bulbs by brightness) 1 = 6 > 7 > 2 = 3 = 4 = 5 > 8 = 9 descending brightness ---  b) After you make your rankings, build circuits to check your answers and list the correct ranking below. Insert images from the simulation to support your sequence. 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page8 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )

Circuit Construction Kit DC This illustrates how the bulbs in series (2, 3, 4, 5) are less bright compared to the bulbs in a single circuit (1, 6). c) Did your rules allow you to correctly rank the bulb brightness? If not, correct your rules in #6. yes d) Did you use any meters to help you make your list? If so, explain why. Yes. I used a Voltmeter to help me make my list. More current through bulb will produce more brightness hence bulb with more current through it will be brighter. 8. If you want to make a flashlight and have two batteries and a lightbulb. a) Predict how you would hook them up to make the brightest flashlight and explain why. Yes, the brightest light is always produced by placing two batteries with voltages that are often additive to one another. This is mostly due to the electrical current being concentrated into one lightbulb. We understand that utilizing batteries, which raise the voltage in the circuit, also raises the current, and that an increase in current is especially noticeable when the brightness of the lightbulb rises. Picture Found Below 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page9 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )

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

Circuit Construction Kit DC b) Build circuits to check your answer and insert images from the simulation for evidence. 4/2/10 Loeblein https://phet.colorado.edu/en/contributions/update-success/5436 page10 (adapted from Argenta Price, Alan Calac Discovering patterns of current and voltage in series and parallel circuits )