10 Electronics Activity Sheet Quarter 2 - MELC 2 Week 2 Electrical Charges REGION VI - WESTERN VISAYAS i STE - ELECTRONICS Activity Sheet No. 2 - Electrical Charges First Edition, 2020 Published in the Philippines By the Department of Education Region 6 - Western Visayas Republic Act 8293, section 176 states that: No copyright shall subsist in any work of the Government of the Philippines. However, prior approval of the government agency or office wherein the work is created shall be necessary for exploitation of such work for profit. Such agency or office may, among other things, impose as a condition the payment of royalties. This Learning Activity Sheet is developed by DepEd Region 6 - Western Visayas. ALL RIGHTS RESERVED. No part of this learning resource may be reproduced or transmitted in any form or by any means electronic or mechanical without written permission from the DepEd Regional Office 6 – Western Visayas. Development Team of Electronics Activity Sheet Writer: Federico B. Barrera Illustrator: Federico B. Barrera Schools Division Quality Assurance Team: Judy B. Dunton, Armida F. Dela Cruz, Lorena D. Panuncio, Joanah V. Rojo, Joebert D. Dorado Schools Division of Capiz Management Team: Salvador O. Ochavo, Jr. Nicasio S. Frio Segundina F. Dollete Shirley A. De Juan Andres D. Quiachon Regional Management Team: Ma. Gemma M. Ledesma, Josilyn S. Solana, Elena P. Gonzaga, Donald T. Genine, Rovel R. Salcedo, Moonyeen C. Rivera, Anita S. Gubalane, Minda L. Soldevilla, Daisy L. Lopez, Joseph M. Pagalaran ii Introductory Message Welcome to STE Electronics 10! The Learning Activity Sheet is a product of the collaborative efforts of the Schools Division of Capiz and DepEd Regional Office VI - Western Visayas through the Curriculum and Learning Management Division (CLMD). This is developed to guide the learning facilitators (teachers, parents and responsible adults) in helping the learners meet the standards set by the K to 12 Basic Education Curriculum. The Learning Activity Sheet is self-directed instructional materials aimed to guide the learners in accomplishing activities at their own pace and time using the contextualized resources in the community. This will also assist the learners in acquiring the lifelong learning skills, knowledge and attitudes for productivity and employment. For learning facilitator: The Electronics Activity Sheet will help you facilitate the leaching-learning activities specified in each Most Essential Learning Competency (MELC) with minimal or no face-to-face encounter between you and learner. This will be made available to the learners with the references/links to ease the independent learning. For the learner: The Electronics Activity Sheet is developed to help you continue learning even if you are not in school. This learning material provides you with meaningful and engaging activities for independent learning. Being an active learner, carefully read and understand the instructions then perform the activities and answer the assessments. This will be returned to your facilitator on the agreed schedule. iii Name of Learner: ________________________________________________________ Grade and Section: ___________________________________Date: ________________ ELECTRONICS ACTIVITY SHEET No. 2 Electrical Charges I. Learning Competency Apply the relationship charge = current x time to new situations or to solve related problems. II. Background Information for Learners In an emergency room of a hospital, a physician is trying to revive the life of a patient using a defibrillator. A defibrillator is a device that gives a high energy electric shock to the heart of someone who is in cardiac arrest. This high energy shock is called defibrillation, which need a large amount of current to restore the heart beat that has already stopped. Electric current is defined as the rate at which charge flows through a surface (the cross section of a wire, for example). A large current is like the energy needed to start a truck engine, whereas a small current is like an energy needed to operate a hand-held calculator. This means that in the truck a large amount of charge moves over a short period of time, while in a calculator, a small amount of charge moves over a long period of time. Mathematically, it is expressed as: q I= t where: I is current q is charge t is time The unit of current is the ampère (A), which is named for the French scientist AndréMarie Ampère (1775–1836). In written languages, it has become customary to write the unit as ampere. Electric charge, (q), on the other hand, is carried by particles called electrons. One electron has a very tiny negative charge and so for practical measurement of electric charge coulombs (C) is used as a unit. Since charge is measured in coulombs and time is measured in seconds, an ampère is the same as a coulomb per second (1A = 1C/s). Every electron has a charge of 1.602176634 × 10−19 C. Reciprocally, the number of electrons needed to produce a coulomb of charge is 6.2415 x 1018 e. A current of one ampere is then the transfer of approximately 6.2415 × 1018 electron charges per second. In summary, I = q/t. Rearranging the equation yields q = (I) (t); and, t = q/I You may meet smaller currents than one ampere. For these currents use milliamps and microamps. 1 A = 1000 milliamp (mA) 1 A = 1 000 000 microamps ((A) 1 Figure 1. Electric Current Direction of Flow of Charge Electron Conductor The more charges that flow through the cross-section of the wire per unit time, the greater is the current. III. Activity Proper ACTIVITY: Counting the passing “monggo” current. Materials needed: 20 cm long drinking straw 40 – 50 pieces monggo beans a ballpen or marker cell phone with a stop watch/timer Procedure: 1. Place the straw flat on a table and put a line mark at the center of the straw. 2. Fully fill the straw with monggo seeds in such a way that when you pop one monggo seed at one end, a different monggo seed should pop out at the other end. 3. Now, pop in 30 monggo seeds one by one through the fully loaded straw and record the time to do it on the table below. 2 Table 1. Record of the number of “ monggo” current. Total number of monggo Time to pop in 30 monggo “Monggo” current seeds that passed through seeds through the straw (Number of monggo passing the marked middle portion of at the center per second) the straw Guide questions 1. What do the monggo seeds represent in this activity? _________________________________________________________________________ _________________________________________________________________________ 2. What does the straw represent in this activity? _________________________________________________________________________ _________________________________________________________________________ 3. How did you compute for the “monggo” current? _________________________________________________________________________ _________________________________________________________________________ Additional II Directions. Study how the following problems are solved. Sample problems 1. A charge of 16 Coulomb passes through the filament of a car headlamp bulb in 4 seconds. What is the current? Answer: Current = Charge/time = 16 C/4s = 4C/s = 4 A 2. A current of 0.5 ampere flows for 15 seconds through a small electric motor. How much charge has passed? Answer: Charge = Current x time = 0.5 A x 15s = 7.5C Going a little Further Directions. Answer the following problems. Show your computation on a separate sheet. 1. What is the current in milliamperes produced by the solar cells of a pocket calculator through which 4.00 C of charge passes in 4.00 h? _________________________________________________________________________ _________________________________________________________________________ 3 2. A defibrillator passes 12.0 A of current through the torso of a person for 0.0100 s. How much charge moves? (b) How many electrons pass through the wires connected to the patient? ___________________________________________________________________ ___________________________________________________________________ 3.. A large lightning bolt had a 20,000-A current and moved 30.0 C of charge. What was its duration? ______________________________________________________________ ______________________________________________________________ V Reflection 1. An electron has an extremely low charge but the aggregation of many electrons over a short period of time may result to a potentially dangerous electric charge. Relate this statement to the saying, “There is strength in numbers”. _________________________________________________________________________ _________________________________________________________________________ 2. How could you possibly protect yourself from large amount of current? _________________________________________________________________________ _________________________________________________________________________ VI. Answer Key ACTIVITY 1: Counting the passing “monggo” current. Table 1. Record of the number of “ monggo” current. Total number of monggo Time to pop in all 30 monggo “Monggo” current seeds that passed thru the seeds thru the straw (Number of monggo passing marked middle portion of the at the center per second) (answer may vary depending straw on the speed of the learner) (answer may vary depending on the speed of the learner) 30 monggo seeds 20 seconds 30 monggo seeds/20 seconds = 1.5 monggo seeds/second 4 Guide questions: 1. The monggo seeds represent the electrons ( charges) flowing through the wire. 2. The straw represents the wire through which the electrons (charges) passes 3. I computed for the “monggo” current by dividing the total number of monggo seeds that passed thru the marked middle portion of the straw with the time to pop in all 30 monggo seeds thru the straw Additional Activity 1. 0.278 mA 2. a) 0.120 C (b) 7.50 × 1017 electrons 3. 1.50 x10 -3 s VII. Other References Giancoli, Douglas C. 2007 Physics Principles with Applications (p493 - 497) Pearson Education South Asia Pte Ltd., Inc..( PHILIPPINE REPRESENTATIVE OFFICE) https://spark.iop.org/electric-charge-and-current-short-history#gref https://www.web-formulas.com/Physics_Formulas/Electric_Current.aspx https://courses.lumenlearning.com/physics/chapter/20-1-current/ https://physics.info/electric-current/ 5
