Republic of the Philippines Department of Education REGION VIII – EASTERN VISAYAS SCHOOLS DIVISION OF LEYTE BURAUEN COMPREHENSIVE NATIONAL HIGH SCHOOL BURAUEN, LEYTE SCHOOL ID: 303353 LEARNING ACTIVITY SHEETS (LAS) IN GENERAL PHYSICS 2 Activity Sheet in Grade 12, SY: 2020-2021 2nd Sem_Quarter 3: WEEK 1 Name of Learner: Duration: Grade and Section: Time Started: Teacher: Time Ended: Date: Week/Day: WEEK 1 Module 1: ELECTRIC CHARGES AND ELECTRIC FIELDS Reference/s: DepEd-Division of Negros Oriental Self Learning Kit in General Physics 1 Learning Competency: 1. Describe using a diagram charging by rubbing and charging by induction STEM_GP12EM-IIIa-1; 2. Explain the role of electron transfer in electrostatic charging by rubbing STEM_GP12EMIIIa-2; 3. Describe experiments to show electrostatic charging by induction STEM_GP12EM-IIIa-3; 4. Calculate the net electric force on a point charge exerted by a system of point charges STEM_GP12EM-IIIa-6; 5. Describe an electric field as a region in which an electric charge experiences a force STEM_GP12EM-IIIa-7; and 6. Calculate the electric field due to a system of point charges using Coulomb’s law and the superposition principle STEM_GP12EM-IIIa-10. General Reminders: Use this activity sheet with care. USE THIS ACTIVITY SHEET IN ANSWERING THE EXERCISES. Read the directions carefully before doing each task. Return this activity sheet to your teacher/ facilitator once you are through with it. PERFOMANCE TASK ACTIVITY 1: WATER BENDING DIRECTIONS: This activity will help you acquire real-life concepts of static electricity. Make a video of you doing the activity or pictures on an A4 bond paper featuring the materials used, procedure and results. Submit it to your General Physics teacher. MATERIALS YOU NEED: 3 Styrofoam cups (you can also use 2 paper cups and an inflated balloon) and a toothpick. Also, this experiment will also require water and someone with dry and clean hair. PROCEDURES: (Answer Questions below. Write your answers on the space provided.) 1. Prepare the set-up by pushing the toothpick at the bottom side of the cups. Leave the toothpick to produce a gentle drop of water after filling the cup. Hold the cup directly over the second cup. Fill the cup (with a toothpick) with water and check if it is leaking steadily. 2. Observe the flow of water from the top cup to the cup below. What are your observations? ____________________________________________________ 3. Rub the third cup on someone with dry hair several times. (This process will help you in acquiring electrical charges). 4. Hold the cup (rubbed against dry hair) near the water stream without getting the cup wet. What happened to the water flow? _____________________________________________________ Then, slowly move the cup away from the stream and observe. Did you observe changes? ___________ If yes, describe the change. _____________________________________________________________________________________________ 5. Try other objects (such as balloon, paper cup or any material) aside from the Styrofoam cup and rub it on a dry and clear hair. What objects have you tried? _____________________________Which of the objects have changed the flow of water? __________________________________________________________________________________________________ Address: Sto. Niño St., San Diego District IX, Burauen, Leyte 6516 Email Address: 303353@deped.gov.ph 1 Republic of the Philippines Department of Education REGION VIII – EASTERN VISAYAS SCHOOLS DIVISION OF LEYTE BURAUEN COMPREHENSIVE NATIONAL HIGH SCHOOL BURAUEN, LEYTE SCHOOL ID: 303353 ACTIVITY 2: QUANTITATIVE PROBLEMS DIRECTIONS: Read and analyze the problems carefully. Write your answers on the space provided below. Use another sheet of paper if needed, attach it here in your LAS. Three charged spheres are at the positions shown in the figure. (a) Find the net electrostatic force at sphere B. (b) Find the net electric field at (4, -3) (a) Find the net electrostatic force at sphere B. A What is/are given? B What is asked? C Are the units consistent with the formula? D How would you draw the problem? E What strategy must be employed? F Solution G What is the conclusion? Address: Sto. Niño St., San Diego District IX, Burauen, Leyte 6516 Email Address: 303353@deped.gov.ph 2 Republic of the Philippines Department of Education REGION VIII – EASTERN VISAYAS SCHOOLS DIVISION OF LEYTE BURAUEN COMPREHENSIVE NATIONAL HIGH SCHOOL BURAUEN, LEYTE SCHOOL ID: 303353 (b) Find the net electric field at (4, -3) A What is/are given? B What is asked? C Are the units consistent with the formula? D How would you draw the problem? E What strategy must be employed? F Solution G What is the conclusion? ASSESSMENT DIRECTIONS: Read each sentences carefully. Write the letter of your choice in the space provided. ______1.The diagram below shows the behavior of the electroscope before and after a positively charged rod is placed near the electroscope knob. This tells us that the movement of electrons is from ______. Address: Sto. Niño St., San Diego District IX, Burauen, Leyte 6516 Email Address: 303353@deped.gov.ph 3 Republic of the Philippines Department of Education REGION VIII – EASTERN VISAYAS SCHOOLS DIVISION OF LEYTE BURAUEN COMPREHENSIVE NATIONAL HIGH SCHOOL BURAUEN, LEYTE SCHOOL ID: 303353 a.rod to leaves c.knob to leaves, then back to knob b.leaves to knob d.leaves to knob, then back to leaves _____2.A glass rod was positively charged when rubbed with a silk cloth. The net positive charge is accumulated because the glass rod a.loses protons c.gains electrons b.loses electrons d.loses electrons _____3.Gravitational forces and electric forces are both a.forces with attractive and repulsive behaviors b.indirectly proportional to the square root of separation between bodies c.directly proportional to the product of the masses and charges d.decreasing when the distance between two bodies is decreasing _____4.At which point is the electric field strength strongest? D A C B _____5.Three spheres were brought together. When Spheres A and B are brought together, they attract. When spheres B and C are brought together, they also repel. Which of the following is true? a.Spheres A & C have same signs c.Spheres A & C have opposite signs b.Spheres B & C have same signs d.Spheres A & B have similar signs _____6.The first object has a charge of +3nC, and the second object has a charge of 6 nC. Which is true about the electric forces between these objects? a.F1on2= 2F2on1 b.3F1on2= 6F2on1 c.-6F1on2=2F2on1 d.F1on2=F2on1 For Nos. 7 to 9, refer to the diagram below: _____7. A positively charged rod was brought near to a metallic plate; what is the type of charge induced along the side facing the rod? a.positive b.negative c.netural d.depends on number of charges _____8.If the positively charged rod was touched on the neutral metallic plate, what is the charge of the plate? a.same b.negative c.positive d.depends on number of charges _____9.After the positively charged rod is placed near the plate, a grounded wire was attached. What is the charge of the plate after the wire is removed? a.negative b.positive c.neutral Address: Sto. Niño St., San Diego District IX, Burauen, Leyte 6516 Email Address: 303353@deped.gov.ph d.depends on number of charges 4 Republic of the Philippines Department of Education REGION VIII – EASTERN VISAYAS SCHOOLS DIVISION OF LEYTE BURAUEN COMPREHENSIVE NATIONAL HIGH SCHOOL BURAUEN, LEYTE SCHOOL ID: 303353 η _____10.The electric flux through the surface at the right is ____ a.zero c.positive b.negative d.unknown _____11.A test charge produced an electric field, E, at point 3 m away from the charge. The point where the field is half its original values is located at a.1.5 m from the charge c.4.5 m from the charge b.6 m from the charge d.at the point of charge _____12.The electric field of a body is directly related to its a.momentum b.kinetic energy c.potential energy d.charge it carries _____13.Charge q1 (26.0 µC) and q2 (-47.0 µC) experienced an electrostatic force of 5.70 N between them at a distance of ____ a.1.39 m b.1.93 m c.2.14 x 10-19 d.1.464 x 10-8 _____14.How many electrons have been removed from a positively charged particle if it has a net charge of 5 x 10-9 C? a.5 x 10-9 electrons c.1 x 10-8 electrons b.2.5 x 10-9 electrons d.incomplete information _____15.A sphere of radius 0.05 m has a charge of 2.0 nC. The charge is said to be located at the center of the sphere. The magnitude of electric field inside the surface is a.zero c.thrice the original value b.twice the original value d.half the original value Prepared by: JUNEDINE MITZE P. QUIÑONES Teacher II QUALITY ASSURANCE TEAM IN SCIENCE MARIE CHARISSE B. GENISTON Teacher II / Member JUNEDINE MITZE P. QUIÑONES Teacher II / Member SHIELA MANGALLON Teacher II / Chairperson RECEIVED AND ACKNOWLEDGED BY: ________________________________________ Parent’s Signature Over Printed Name Address: Sto. Niño St., San Diego District IX, Burauen, Leyte 6516 Email Address: 303353@deped.gov.ph 5
