LESSON 4 VOLTS, CURRET, and RESISTANCE, Continued

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LESSON 4 VOLTS, CURRET, and RESISTANCE, Continued

Research Experience for Teacher

LESSON 4 – VOLTS, CURRET, AND RESISTANCE

LESSON OVERVIEW - Summary of the task, challenge, investigation, career-related scenario, problem, or community link. This is an inquiry lesson. All the lesson objectives are designed to illustrate a mastery of grade level expectations based on the embedded conceptual strand that states: Understandings about scientific inquiry and the ability to conduct inquiry are essential for living in the 21st century. The lesson will lead the students to more thorough understanding of how electric energy moves through different objects. The class will use a hand-on, inquiry lab to establish a quantitative way to measure the flow of electricity through a simple circuit with multiple resisters in place. The students will use a multimeter to measure the current (I) and voltage (V) at several locations on the circuits they build. They will use the information they gather to formulate an idea about the relationship between voltage and resistance and the brightness of the flashlight bulbs. The students will then be asked to predict how it will work on a bigger scale, like their own house. The hands-on, inquiry portion of the class will be followed by a short lecture meant to shore up the vocabulary and help with the formulation of new ideas. The students will most likely have to finish their analysis and reflection as homework or the following day in class. A separate lab sheet has been prepared for the honors class that requires some calculations of the resistance found in the circuits they have built.

STANDARDS - Identify what you want to teach. Reference State, Common Core, ACT College Readiness Standards and/or State Competencies. GLE 0607.Inq.2 - Use appropriate tools and techniques to gather, organize, analyze, and interpret data. GLE 0607.Inq.3 - Synthesize information to determine cause and effect relationships between evidence and explanations. GLE 0607.Inq.5 - Communicate scientific understanding using descriptions, explanations, and models.

OBJECTIVE - Clear, Specific, and Measurable – NOT ACTIVITIES - Student-Friendly Describe electric current. Describe voltage and resistance and their relationship to electric current.

ASSESSMENT/EVALUATION - Students show evidence of proficiency through a variety of assessments - Aligned with the Lesson Objective. Formative/Summative. Performance-Based/Rubric

Students understanding of the key concepts will be demonstrated by their ability to successfully complete the lab write-up sheet. The students predictions of how their home would run with their appliances plugged into either parallel or series circuits should not only verify they understand the concepts, but also indicate their level of mastery of the glade level expectations. LESSON 4 – VOLTS, CURRET, AND RESISTANCE, continued

MATERIALS - Aligned with the Lesson Objective - Rigorous & Relevant

 Forces in Nature PowerPoint  battery, 6 V  multimeter with leads  flashlight bulb with holder (3)  wire leads, copper, insulated with alligator clips attached (5)

ACTIVATING STRATEGY - Motivator/Hook - An Essential Question encourages students to put forth more effort when faced with a complex, open-ended, challenging, meaningful and authentic questions. The class will start with a Bellringer question. The question will be on the board as the students enter the room. They should go to their seats and begin answering the questions as soon as the bell rings. This procedure was taught during the first few weeks of school and has been practiced almost daily. The students should understand the expectations be able to follow the procedure with out direction. The Bellringer questions are: How would you describe this water! Record your answers or draw an explanatory picture for later reference in your Interactive Science Notebook. The class will be given time to formulate their answers and record them in their Interactive Science Notebooks (ISN’s). The students will share their answers with their neighbors, then the neighbors will nominate a classmate to share their ideas. Two to three student should be given a chance to share. The teacher will leave the answer open and revisit the question toward the end of class.

GUIDED & INDEPENDENT PRACTICE – “We Do”-“You Do” - Encourage Higher Order Thinking & Problem Solving, Relevance As stated previously, the teacher will divide the class into groups. It will be beneficial to divide the visual/special learners and the kinesthetic learners evenly through the group to facilitate the process and provide the best opportunities for learning. Each group of 3 - 5 students will be given a kit with the materials needed to construct a simple circuit. The groups will be asked ….. The teacher will explain the day’s objectives after the class has finished its discussion of the Bellringer. The day’s objectives are: Describe electric current. Describe voltage and resistance and their relationship to electric current. Before transitioning to the lab for the remainder of the class, the teacher will introduce the Circuits 101 activity. The teacher will explain that every student is expected to provide a completed activity sheet showing his or her own work. The teacher will divide the class into groups. It will be beneficial to divide the visual/special learners and the kinesthetic learners evenly through the group to facilitate the process and provide the best opportunities for learning.

Research Experience for Teachers LESSON 4 – VOLTS, CURRET, AND RESISTANCE, continued The teacher will remind the students of the safety precaution they need to take while conducting this simple lab. They need to be aware that even the simple, 6v batteries can cause some wires to get hot, and if they notice this happening, they should disconnect the battery immediately. The need to be aware that the light bulbs will get hot and they should be handled with care. They should also understand that the bulbs are made of glass and that they could be cut if the glass breaks. In the event there is an accident, they should contact the teacher immediately and allow the teacher to clean up the broken glass. The teacher will need to demonstrate the use of the multimeter. This should include what setting tit should be placed on for the two different types of measurements that must be made. As the students finish, they will be instructed to clean up their stations, making sure to remove all the leads from the batteries.

INSTRUCTION - Step-by-Step Procedures-Sequence - Discover/Explain – Direct Instruction, Modeling Expectations – “I Do”, Questioning/Encourages Higher Order Thinking, Grouping Strategies

Class will continue with a short period of direct instruction once all the students have completed all their measurements and recorded the necessary information. It will not be necessary for them to have completed the conclusions section of the lab write-up. The lecture and class discussion will provide some additional information that might be helpful in their conclusion. The teacher will lead the class through the

CLOSURE - Reflection/Wrap-Up - Summarizing, Reminding, Reflecting, Restating, Connecting

Students will return to their seats to reflect on the activity and relate it to their lives at home by answering the following:

Based on your results, what do you think might happen if too many electrical appliances are plugged into the same series circuit? What might happen if too many electrical appliances are plugged into the same parallel circuit? Design a method to explain your reasoning.

CROSS-CURRICULAR CONNECTIONS There is direct connection to language arts as the students will be required to properly structure their sentences during the Guided & Independent Practice and in particular while preparing the written response for their conclusion. The honors group will use their math skills to further illustrate the relationships between current, voltage, and resistance.

NOTES

Research Experience for Teachers Skills Practice DATASHEET FOR CHAPTER LAB Circuitry 101

There are two basic types of electric circuits. A series circuit connects all of the parts in a single loop, and a parallel circuit connects each part on a separate branch. A switch wired in series with the energy source can control the whole circuit. If you want each part of the circuit to work on its own, the loads must be wired in parallel. In this lab, you will use an ammeter to measure current and a voltmeter to measure voltage.

OBJECTIVES Build a series circuit and a parallel circuit. Measure current in amps (A) and the voltage in volts (V) throughout the simple circuit

MATERIALS

• energy source—dry cell(s) • light bulbs • wire, insulated, 15 cm lengths with alligator • multimeter clips • light-bulb and holders (3)

SAFETY INFORMATION

PROCEDURE 1. Build a series circuit with an energy source, a switch, and three light bulbs. Draw a diagram of your circuit. Caution: Always leave the switch open when building or changing the circuit. Close the switch only when you are testing or taking a reading.

Circuitry 101 continued 2. Test your circuit. Do all three bulbs light up? Are all bulbs the same brightness? What happens if you carefully unscrew one light bulb? Does it make any difference which bulb you unscrew? Record your observations. ______3. Connect the ammeter between the power source and the switch. Close the switch, and record the current (I), in amps, on your diagram. Be sure to show where you measured the current. 4. Reconnect the circuit so that the multimeter is between the first and second bulbs. Record the current (I), in amps, as you did in step 3. 5. Move the multimeter so that it is between the second and third bulbs, and record the current (I) in amps again. 6. Remove the multimeter from the circuit. Change the setting on the multimeter so it can measures DC voltage. Connect the multimeter to the two ends of the power source. Record the voltage (V) on your diagram. 7. Use the multimeter to measure the voltage across each bulb. Record each reading. 8. Take apart your series circuit. Reassemble the same items so that the bulbs are wired in parallel. (Note: The switch must remain in series with the power source to be able to control the whole circuit.) Draw a diagram of your circuit.

Circuitry 101 continued 9. Test your circuit, and record your observations, as you did in step 2. ______10. Set the multi meter back to amps. Connect the multimeter between the power source and the switch. Record the current (I), in amps. 11. Reconnect the circuit so that the multimeter is right next to one of the three bulbs. Record the current (I) in amps. 12. Repeat step 11 for the two remaining bulbs. 13. Remove the multimeter from your circuit. Set the multimeter so it can measure DC volts. Connect the multimeter to the two ends of the power source. Record the voltage (V). 14. Measure and record the voltage (V) across each light bulb.

ANALYZE THE RESULTS 1. Recognizing Patterns Was the current (I) the same at all places in the series circuit? Was it the same everywhere in the parallel circuit? ______2. Analyzing Data For each circuit, compare the voltage across each light bulb with the voltage at the power source. ______3. Identifying Patterns What is the relationship between the voltage at the power source and the voltages at the light bulbs in a series circuit? ______

Circuitry 101 continued

DRAW CONCLUSIONS 4. Interpreting Information Why did the bulbs differ in brightness? ______5. Making Predictions Based on your results, what do you think might happen if too many electrical appliances are plugged into the same series circuit? What might happen if too many electrical appliances are plugged into the same parallel circuit? Design a method to explain your reasoning. ______Skills Practice DATASHEET FOR CHAPTER LAB Circuitry 101 - Honors

There are two basic types of electric circuits. A series circuit connects all of the parts in a single loop, and a parallel circuit connects each part on a separate branch. A switch wired in series with the energy source can control the whole circuit. If you want each part of the circuit to work on its own, the loads must be wired in parallel. In this lab, you will use an ammeter to measure current and a voltmeter to measure voltage. For each circuit, you will use Ohm’s law (resistance equals voltage divided by current) to determine the overall resistance.

OBJECTIVES Build a series circuit and a parallel circuit. Measure current in amps (A) and the voltage in volts (V) throughout the simple circuit Use Ohm’s law to calculate the resistance of a circuit from voltage and current.

MATERIALS • energy source—dry cell(s) • light bulbs • wire, insulated, 15 cm lengths with alligator • multimeter clips • light-bulb and holders (3)

SAFETY INFORMATION

PROCEDURE 1. Build a series circuit with an energy source, a switch, and three light bulbs. Draw a diagram of your circuit. Caution: Always leave the switch open when building or changing the circuit. Close the switch only when you are testing or taking a reading.

Circuitry 101 continued 2. Test your circuit. Do all three bulbs light up? Are all bulbs the same brightness? What happens if you carefully unscrew one light bulb? Does it make any difference which bulb you unscrew? Record your observations. ______3. Connect the ammeter between the power source and the switch. Close the switch, and record the current (I), in amps, on your diagram. Be sure to show where you measured the current. 4. Reconnect the circuit so that the multimeter is between the first and second bulbs. Record the current (I), in amps, as you did in step 3. 5. Move the multimeter so that it is between the second and third bulbs, and record the current (I) in amps again. 6. Remove the multimeter from the circuit. Change the setting on the multimeter so it can measures DC voltage. Connect the multimeter to the two ends of the power source. Record the voltage (V) on your diagram. 7. Use the multimeter to measure the voltage across each bulb. Record each reading. 8. Take apart your series circuit. Reassemble the same items so that the bulbs are wired in parallel. (Note: The switch must remain in series with the power source to be able to control the whole circuit.) Draw a diagram of your circuit.

Circuitry 101 continued 9. Test your circuit, and record your observations, as you did in step 2. ______10. Set the multimeter back to amps. Connect the multimeter between the power source and the switch. Record the current (I), in amps. 11. Reconnect the circuit so that the multimeter is right next to one of the three bulbs. Record the current (I) in amps. 12. Repeat step 11 for the two remaining bulbs. 13. Remove the multimeter from your circuit. Set the multimeter so it can measure DC volts. Connect the multimeter to the two ends of the power source. Record the voltage (V). 14. Measure and record the voltage (V) across each light bulb.

ANALYZE THE RESULTS 1. Recognizing Patterns Was the current the same at all places in the series circuit? Was it the same everywhere in the parallel circuit? ______2. Analyzing Data For each circuit, compare the voltage across each light bulb with the voltage at the power source. ______3. Identifying Patterns What is the relationship between the voltage at the power source and the voltages at the light bulbs in a series circuit? ______4. Analyzing Data Use Ohm’s law and the readings for current (I) and voltage (V) at the power source for both circuits to calculate the total resistance (R) in both the series and parallel circuits.

DRAW CONCLUSIONS 5. Drawing Conclusions Was the total resistance for both circuits the same? Explain your answer. ______6. Interpreting Information Why did the bulbs differ in brightness? ______Circuitry 101 continued

7. Making Predictions Based on your results, what do you think might happen if too many electrical appliances are plugged into the same series circuit? What might happen if too many electrical appliances are plugged into the same parallel circuit? Design a method to explain your reasoning. ______

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