THE ENERGY CHALLENGE

Transcription

1 THE ENERGY CHALLENGE TSC Scored Activity 1 Date submitted:... Student identification Name:... Address: Tel.: Mark:... /100

2 TSC THE ENERGY CHALLENGE This scored activity was produced by the Société de formation à distance des commissions scolaires du Québec (SOFAD). Production Team Project coordinator for the English version: Project coordinator for the French version: Author: Illustrations: Content revision: Translation: Layout and computer graphics: Proofreading: Jean-Simon Labrecque Alain Pednault (SOFAD) Interscience Marc Tellier Judith Sévigny Claudia de Fulviis Daniel Rémy (I. D. Graphique inc.) Claudia de Fulviis Alain Pednault (SOFAD) This translation was financed by the Ministère de l Éducation, du Loisir et du Sport du Québec. Part of this financing is from the Canada-Quebec bilateral agreement related to minority language education and second languages instruction. Despite the following statement, SOFAD authorizes adult education centres using the related learning guide to reproduce this scored activity. SOFAD, 2013 All rights for translation and adaptation, in whole or in part, are reserved for all countries. Any reproduction by mechanical or electronic means, including micro-reproduction, is prohibited without the written permission of a duly authorized representative of the Société de formation à distance des commissions scolaires du Québec (SOFAD). SOFAD

3 SCORED ACTIVITY 1 Most education centres require that students obtain an average mark of 60% or higher in order to write the official examination. Scored Activity 1 covers the subject matter in learning sequences 1, 2 and 3 of the The Energy Challenge learning guide. Once you have completed this activity, send it to your tutor together with any related documents. SOFAD 3

4 TSC THE ENERGY CHALLENGE Instructions Fill in the Identification section. Carefully read each question before answering it. Write your answers in the appropriate spaces and give complete solutions, as applicable. The weighting for each question is indicated to the right of each section of the scored activity. You may use a calculator. 4 SOFAD

5 SCORED ACTIVITY 1 Scored Activity 1 /100 points Submit After learning sequences 1, 2 and 3. Essential knowledge covered Energy resources; static electricity; electrical charge; electrical field; Coulomb's law; atomic model; subatomic particles; electrical circuits; Ohm's law; power supply, conduction, insulation, protection, control and energy transformation functions; diagrams; and symbols A. Explicit Evaluation of Knowledge 1. Multiple-choice questions /15 points 1. Which of the following consumes the most energy in Québec? a) A television set b) A microwave oven c) An electric baseboard heater d) A refrigerator 2. Which of the following needs requires the least energy? a) Keeping warm b) Communicating with others c) Getting around d) Feeding oneself 3. What energy source, which was used to heat the water in steam engines, was at the origin of the Industrial Revolution in Europe in the 18th century? a) Uranium b) Diesel gas c) Petroleum d) Coal 4. Which of the following statements best describes the Rutherford atomic model? a) Positive electrons orbiting around a negative nucleus. b) Positive electrons in a positive nucleus. c) Negative electrons orbiting around a positive nucleus. d) Negative electrons in a positive nucleus. SOFAD 5

6 TSC THE ENERGY CHALLENGE 5. You rub the end of a plastic rod with a piece of wool and the wool acquires a positive electrical charge. Why is this? a) The wool acquired protons. b) The wool acquired electrons. c) The wool lost protons. d) The wool lost electrons. 6. When is an object electrically neutral? a) When it has no electrical charge. b) When it has as many positive charges as negative charges. c) When it has lost all of its electrical charges. d) When it can no longer be electrically charged. 7. What is the electrical charge of each of the two spheres represented below? a) Sphere A is positive and sphere B is negative. b) Sphere A is negative and sphere B is positive. c) Both spheres are positive. d) Bother spheres are negatives. A B 8. The physicist Charles Coulomb succeeded in determining the magnitude of the force exerted between two electrical point charges. We know that two electrical point charges of one coulomb placed one metre apart attract or repel each other with a force of newtons. With what force will two small spheres with charges of 4.0 mc and 5.0 mc respectively if they are placed 10.0 cm apart? a) 0.06 N b) 1.8 N c) 18 N d) 20 N 9. Complete the following statement: "In a resistor powered by a battery,." a) the positive charges move towards the battery's positive terminal. b) the positive charges move towards the battery's negative terminal. c) the electrons move towards the battery's negative terminal. d) the electrons move towards the battery's positive terminal. 6 SOFAD

7 SCORED ACTIVITY What is an ore? a) It is a rock with an ore content that can be exploited commercially. b) It is a component of all rocks. c) It is a crystalline rock. d) It is a non-crystalline rock. 11. What is the maximum voltage across the terminals of a 120-V alternating current outlet? a) 120 V b) 170 V c) 185 V d) 240 V 12. The circuit opposite consists of a light bulb powered by a 1.5-V battery with negligible internal resistance and a unipolar switch. Which of the following statements is TRUE? a) When the circuit is open, the voltage across the switch's terminals is 1.5 V. b) When the circuit is open, the voltage across the light bulb's terminals is 1.5 V. c) When the circuit is closed, the voltage across the light bulb's terminals is 0 V. e = 1.5 V d) When the circuit is closed, the voltage across the switch's terminals is 1.5 V. 13. A copper wire has a resistance of 0.12 W. What will be the resistance of a copper wire that is twice as long and has a diameter that is twice as small? a) 0.01 W b) 0.12 W c) 0.06 W d) 0.96 W 14. The graph opposite shows the change in the current intensity as a function of the voltage across the terminals of as circuit element. What can you say about the resistance of this circuit element? a) The resistance increases with the voltage. b) The resistance decreases with the voltage. c) The resistance is constant. d) The resistance decreases when the current intensity increases. I 0 I = f (V) V SOFAD 7

8 TSC THE ENERGY CHALLENGE 15. A circuit is formed with a battery and a light bulb whose resistance is 6.0 W when subject to a current of 500 ma. What is the battery's emf? a) 3 V b) 5 V c) 6 V d) 12 V 2. Short-answer questions /10 points 16. Describe the energy chain in an incandescent light bulb. 17. What did the English scientist John Dalton name the basic particles which formed the cornerstone of his theory of the composition of matter? 18. You rub a plastic rod with a piece of wool and then you bring the rubbed part of the rod close to a suspended small metallic sphere with a negative charge. Will the sphere be attracted or repelled by the rod? 19. Two small spheres each with a charge Q and placed 5 cm apart repel each other with a force F. What will happen to this force is the spheres are placed 20 cm apart after their charges have been doubled? 20. Two small metallic spheres with charges of mc and 8.0 mc respectively are placed 5.0 cm apart after being brought into contact. Calculate the magnitude of the force of repulsion between the spheres. 21. What is the sign of the electrical charge that builds up on the pointy end of a lightining rod when a cumulonimbus cloud whose base is negatively charged approaches it? 8 SOFAD

9 SCORED ACTIVITY You insert two copper rods into a lemon. a) What will be the emf reading on a voltmeter that is connected to the rods? b) Explain this result. 23. A circuit consists of a direct current source of variable intensity and a resistor. The results obtained by measuring the voltage across the resistor and the intensity of the current that flows through it were used to draw the graph opposite. What is the resistance of this resistor? I (A) I = f (V) V ( V ) 24. What is the resistance of the tungsten filament in an electrical light bulb if a 0.50-A currrent flows through it and the voltage is 12 V? 25. A 0.06-A current flows though a resistor of 100 W when the resistor is connected to a 6-V battery. If you replaced the resistor by a 200-W resistor, how would this affect: a) the current intensity? b) the emf of the source? SOFAD 9

10 TSC THE ENERGY CHALLENGE B. Evaluation Sequence: Installing a Lightning Rod Goal To implement his or her problem-solving skills and knowledge of energy, electrostatics and electrokinetics by proposing the installation of a lightning rod on a house located in a rural area Ever since Benjamin Franklin invented the lightning rod, most isolated or tall structures are equipped with this device for protection against lightning. As you know, a lightning rod does not attract lightning. It does, however, provide a path for the electrical charges that make up the lightning. This device protects against damages related to lightning strikes. Scenario You work as a technician for a company that specializes in the installation of lightning rods. You are asked to install a lightning rod on a house located in a rural area. The client is unhappy with the fact that lightning recently struck his house and damaged several electrical appliances; his insurance company has asked him to install a device to prevent such an occurrence from happening again. Your task You will provide the homeowner with: an explanation about how lightning forms; a sketch of the installation of the lightning rod on his house; a schematic description of the trajectory of the electrical charges in the lightning rod. Electricity in the air /20 points Once you meet the client, you take a few minutes to carry out a visual inspection of the outside of his home. During this time, you explain the phenomenon of lightning. a) Explain and provide a diagram of how an electrostatic charge forms on the ground in the presence of a storm cloud (cumulonimbus) whose base is negatively charged. Explanation: 10 SOFAD

11 SCORED ACTIVITY 1 Diagram: During your inspection, you notice that there is a solar panel at the very top of the roof of the house. You suspect that lightning has probably struck the house at this spot, and that the excess energy damaged some of the electrical appliances. b) Explain to the client why the lightning bolt struck the solar panel and not another part of the house. SOFAD 11

12 TSC THE ENERGY CHALLENGE Components of a lightning rod /20 points You suggest to the client that he have a lightning rod installed near his solar panel, and that the pointy end of the rod be higher than the panel. In this way, if lightning were to strike again, it would follow this path. You explain how the device is made. In the table below, list the four main components of a lightning rod. For each one, name an important characteristic and describe its role in the installation. Components of a lightning rod Component Characteristic Role 12 SOFAD

13 SCORED ACTIVITY 1 Installation of the lightning rod /15 points Now, draw a sketch of the installation of the lightning rod on the house; remember to identify the four components of the device in your sketch. The trajectory of the charges /20 points Now draw the elements that are involved in the production and channelling of the electrical charges produced during a storm, that is: the cloud, the ground, the house and the lightning rod. Indicate the trajectory of the charges, from the time they are formed until they drained to the ground. SOFAD 13

14 TSC THE ENERGY CHALLENGE Review of Competencies What is a competency? A competency is defined as the ability to effectively use a set of resources, such as knowledge, skills and attitudes. In this course, you will develop the following subject-specific competencies: Seeks answers or solutions to scientific or technical problems (C1) Makes the most of his/her knowledge of science and technology (C2) Communicates using the languages of science and technology (C3) The third competency is not evaluated separately, but as part of the other two competencies. With regard to learning sequences 1, 2 and 3, which you have completed, indicate whether you were able to develop the following key features of the competencies. Self-evaluation of competency development Activity Competency Key features developed Yes No In part I charged objects by friction and by contact. I charged objects by induction. 2.2 Electrification C2 and C3 I described the transfer of charges that occurs when objects are charged. I wrote a clear and organized discussion. I wrote a clear and organized conclusion. I used the correct scientific vocabulary. 14 SOFAD

15 SCORED ACTIVITY 1 Activity Competency Key features developed Yes No In part 2.3 Coulomb's Law C2 I analyzed the experimental data relating to electrical force. I deduced Coulomb's law from experimental data. 2.5 An Electrifying Party C2 and C3 I explained the phenomenon of attraction between a wall and a balloon that was rubbed. I wrote a clear and organized discussion. I wrote a clear and organized conclusion. I used the correct scientific vocabulary. I used a multimeter to measure voltages. I used a multimeter to measure current intensities. 3.2 Measurements and Ohm's Law C2 and C3 I used a multimeter to measure resistances. I checked the accuracy of my measurements using Ohm's law. I wrote a clear and organized discussion. I wrote a clear and organized conclusion. I used the correct scientific vocabulary. SOFAD 15

16 TSC THE ENERGY CHALLENGE Activity Competency Key features developed Yes No In part I correctly mounted my lemon-cell battery. 3.4 The Lemon Battery C2 and C3 I obtained a measurable voltage in my battery's terminals. I wrote a clear and organized discussion. I wrote a clear and organized conclusion. I used the correct scientific vocabulary. I designed the electrical circuit for a functional alarm system. 3.5 My Alarm System C1 and C3 I mounted the circuit for an effective alarm system. I wrote a clear and organized discussion. I wrote a clear and organized conclusion. I used the correct scientific vocabulary. I used symbolic and graphical language in my circuit diagram. 16 SOFAD

17

18

19

20 TSC THE ENERGY CHALLENGE Student's questions or comments Tutor's remarks December 2013