Física y química 3º E.S.O.

1. Física y química 3º E.S.O. THIRD TERM Unit 5: Electricity and magnetism U_5_4_Electric fields U.5_4 d1

2. Bloque 4. El movimiento y las fuerzas. 4.1. Las fuerzas. Efectos de las fuerzas. 4.2. Fuerzas de especial interés: peso, normal, rozamiento, fuerza elástica. 4.3. Principales fuerzas de la naturaleza: gravitatoria, eléctrica y magnética. Criterios de evaluación C.E.4.8. Conocerlos tipos de cargas eléctricas, su papel en la constitución de la materia y las características de las fuerzasque se manifiestan entre ellas. . Estándares de aprendizaje evaluables E.A.4.8.1. Explica la relación existente entre las cargas eléctricas y la constitución de la materia y asocia la carga eléctrica de los cuerpos con un exceso o defecto de electrones. E.A.4.8.2. Relaciona cualitativamente la fuerza eléctrica que existe entre dos cuerpos con su carga y la distancia que los separa, y establece analogías y diferencias entre las fuerzas gravitatoria y eléctrica. Criterios de evaluación C.E.4.9. Interpretar fenómenos eléctricos mediante el modelode cargaeléctricay valorar la importanciade la electricidaden la vida cotidiana. Estándares de aprendizaje evaluables E.A.4.9.1. Justifica razonadamente situaciones cotidianas en las que se pongan de manifiesto fenómenos relacionados con la electricidad estática. Criterios de evaluación C.E.4.10. Justificar cualitativamentefenómenos magnéticos y valorarla contribución del magnetismo en el desarrollo tecnológico. . Estándares de aprendizaje evaluables E.A.4.10.1. Reconoce fenómenos magnéticos identificando el imán como fuente natural del magnetismo y describe su acción sobre distintos tipos de sustancias magnéticas. E.A.4.10.2. Construye, y describe el procedimiento seguido pare ello, una brújula elemental para localizar el norte utilizando el campo magnético terrestre. Criterios de evaluación C.E.4.11. Comparar los distintostiposde imanes, analizar su comportamiento y deducir medianteexperienciaslas característicasde lasfuerzas magnéticas puestas de manifiesto, asícomosurelación conla corriente eléctrica. Estándares de aprendizaje evaluables E.A.4.11.1. Comprueba y establece la relación entre el paso de corriente eléctrica y el magnetismo, construyendo un electroimán. E.A.4.11.2. Reproduce los experimentos de Oersted y de Faraday, en el laboratorio o mediante simuladores virtuales, deduciendo que la electricidad y el magnetismo son dos manifestaciones de un mismo fenómeno. U.5_4 d2

3. Lesson 1 - Basic Terminology and Concepts Lesson 2 - Methods of Charging Lesson 3 - Electric Force Lesson 4 - Electric Fields U.5_4 d3

4. Lesson 4 - Electric Fields U.5_4 d4

5. 5.4.1. The concept of field in science U.5_4 d5

6. 5.4.1. The concept of field in science The action-at-a-distance forces are sometimes referred to as field forces. The concept of a field force is utilized by scientists to explain the phenomenon that occurs so that forces are produced even in the absence of physical contact. U.5_4 d6

7. 5.4.1. The concept of field in science The concept of a field force is utilized by scientists to explain the phenomenon that occurs so that forces are produced even in the absence of physical contact. Think of an area in the Universe in with there is no matter. This area remains unaltered. U.5_4 d7

8. 5.4.1. The concept of field in science The presence of an object (M1) creates an alteration of the space in the region that surrounds it. We call this alteration gravitational field. U.5_4 d8

9. 5.4.1. The concept of field in science Any other object (M2) that is in that space feels the effect of the mass (M1). U.5_4 d9

10. 5.4.1. The concept of field in science Unaltered area in the Universe Any other object that is in that space feels the effect of the mass The presence of a mass creates a gravitational field. U.5_4 d10

11. 5.4.2. The gravitational field Field, in physics, is a region in which each point is affected by a force Objects fall to the ground because they are affected by the force of earth’s gravitational field (see gravitation) U.5_4 d11

12. 5.4.2. The gravitational field Field, in physics, is a region in which each point is affected by a force We cannot see or touch this field, but we can try to represent it using field lines or lines of force U.5_4 d12

13. 5.4.2. The gravitational field Field, in physics, is a region in which each point is affected by a force. We cannot see or touch this field, but we can try to represent it using field lines or lines of force A gravitational field line is a line that indicates the direction of the gravitational force that would act on a test mass placed in the field. U.5_4 d13

14. 5.4.2. The gravitational field A gravitational field diagram represents the gravitational field lines. The test mass is not drawn. Earth's Gravitational Field U.5_4 d14

15. 5.4.2. The gravitational field Newton's law of gravitation implies that the gravitational force decreases according to the inverse square law U.5_4 d15

16. 5.4.3. The electric field Field, in physics, is a region in which each point is affected by a force An electric field surrounds an electric charge When another charged particle is placed in that region, it experiences an electric force that either attracts or repels it. U.5_4 d16

17. 5.4.3. The electric field When the object is positively charged, electric field lines extend radially outward from the object. When the object is negatively charged, the lines extend radially inward. http://www.physicsvideos.net/ An electrostatic Van de Graaff generator demonstrates radial electric field lines when it is energized with streamers attached to it. U.5_4 d17

18. 5.4.3.a. The electric field of a positive charge U.5_4 d18

19. 5.4.3.a. The electric field of a positive charge A positively charged particle, Q, produces an electric field in the region of space around it. U.5_4 d19

20. 5.4.3.a. The electric field of a positive charge A positively charged particle, Q, produces an electric field in the region of space around it If a small test charge, q0, is placed in the field, it will experience a force directed away from the charge U.5_4 d20

21. 5.4.3.a. The electric field of a positive charge The electric field of a point charge points radially away from a positive charges Field lines U.5_4 d21

22. 5.4.3.a. The electric field of a positive charge Inverse square law, like the gravitational field U.5_4 d22

23. 5.4.3.b. The electric field of a negative charge A negatively charged particle, Q, produces an electric field in the region of space around it. If a small test charge, q0, is placed in the field, it will experience a force that is always directed towards the negative charge U.5_4 d23

24. 5.4.3.b. The electric field of a negative charge The electric field direction about a negative charge is always directed towards it U.5_4 d24

25. 5.4.3.c. Other electric fields A negative and a positive charges The lines are directed away from the positive charge and toward the negative charge U.5_4 d25

26. 5.4.3.c. Other electric fields A negative and a positive charges The lines are directed away from the positive charge and toward the negative charge U.5_4 d26

27. 5.4.3.c. Other electric fields Two positive charges The lines are directed away from both positive charges U.5_4 d27

28. 5.4.3.c. Other electric fields Two positive charges The lines are directed away from both positive charges U.5_4 d28

29. 5.4.3.c. Other electric fields A negative and a positive charges U.5_4 d29

30. 5.4.3.c. Other electric fields A negative and a positive charges U.5_4 d30

31. 5.4.3.c. Other electric fields Two positive charges vs. two negative charges U.5_4 d31

32. 5.4.3.c. Other electric fields The lines are directed away from the positive charges and toward the negatives charges U.5_4 d32

33. 5.4.3.c. Other electric fields Combinations of charges. Note that, while the lines are less dense where the field is weaker, the field is not necessarily zero where there are no lines. In fact, there is only one point within the figures below where the field is zero. Can you find it? U.5_4 d33

34. 5.4.3.c. Other electric fields What is the electric field between two oppositely charged parallel plates? Remember: U.5_4 d34

35. 5.4.3.c. Other electric fields What is the electric field between two oppositely charged parallel plates? We use a small test charge q0 to find out if an electric field is present Remember: U.5_4 d35

36. 5.4.3.c. Other electric fields What is the electric field between two oppositely charged parallel plates? Remember: U.5_4 d36

37. 5.4.3.c. Other electric fields What is the electric field between two oppositely charged parallel plates? U.5_4 d37