Download 1.3 Notes

Physics in Context
Chapter 1.3 Notes
1. Two universal forces in nature are __________________________ and ________________________.
2. They are universal because each force acts the same _____________________ in the universe.
3. __________________________ act between two or more masses.
4. ___________________________ act between two or more charges.
5. __________________________________________ is every object in the universe attracts every other
object with a force that (for two bodies) is directly proportional to the mass of each body and that is
inversely proportional to the square of the distance between them.
6. Video – What keeps the planets in orbit?
7. Video – What is the strength of gravity determined by?
8. The gravitational force is exerted _____________ on both masses but the direction of the force is
different for both masses.
9. The gravitational force is always an _____________________ force.
10. The property of an object that causes electrical force is called _________________.
11. There are two types of charges; __________________________ and _____________________.
12. Two objects with the same charge, both positive or both negative, _____________ each other.
13. Two objects with opposite charges _________________ each other.
14. Video – Why is it so difficult to study atoms?
15. The origin of electric charge is found in the __________.
16. The nucleus of an atom contains most of the mass, in the neutrons and _________________.
17. Neutrons have no charge and so they are ________________.
18. Protons have a ________________ charge.
19. The nucleus is surrounded by a cloud of ________________.
20. Electrons have a _____________ charge.
21. The charge of the electron is ____________ to the charge of the proton.
22. The force of _______________ between the proton and electron is what keeps the electron bound to the
nucleus.
23. A normal atom has no _____________, since it has an equal amount of electrons and protons.
24. You can transfer charge from one object to another because the outermost electrons in the atoms of
some substances are not tightly ______________ to the nucleus and can be removed.
25. The net electrical charge in an isolated system never changes; This is the principle of
_________________________________.
26. ___________________________ states that the electrical force between two charged bodies is directly
proportional to the charge on each body and inversely proportional to the square of the distance between
them.
27. The charge on one electron or proton is 1.6 x 10 -19; This is called the
____________________________.
28. A _________ is an imaginary construction used by scientists to help them understand and predict how
forces are transmitted from one object to another.
29. The _________________ of a field is shown with arrows.
30. Where the lines are close together, the magnitude of the field is _____________.
31. Where the lines are far apart, the magnitude of the field is __________.
32. Field lines can only be shown in two dimensions, but true electric fields are _____________________.
33. If you move a charge against an electric field, you must exert a _____________ on the charge.
34. The charge possesses a potential because if it is released, the charge will ________________ towards its
original position; the field creates an ______________________________________.
35. In a uniform electric field of magnitude E, the electrical potential difference VAB between the points A
and B, separated by a distance of d is the following: ___________________________
36. The unit of measurement for electric potential difference is the __________.
37. Electric potential difference is sometimes simply called __________________.
38. _____________ is the main move in electrical systems, like pressure is the main mover in fluid systems.
39. A flow of charge is called an electrical ________________.
40. In the electrical system, current can be maintained with a ____________________.
41. Video – How much energy did NASA create in outer space using a tether?
42. Video – What caused the tether to break?
43. Electrical systems contain four major components:
1. ____________________
2. ____________________
3. ____________________
4. ____________________
44. The _________ in an electrical system is usually an appliance or machine such as an electric motor.
45. An electrical __________________ is a material through which charge can easily flow.
46. The ____________________________ can be a switch that turns the current on or off.
47. An _____________________ is a closed path for current to flow created by connecting voltage sources,
conductors, control elements, and loads.
48. There are two types of current: ______________________ and _________________________.
49. In direct current (DC), the electric charge flows in _________ direction.
50. In alternating current (AC), the electric charge flows _____________________________.
51. Batteries produce ________________________ and alternators produce _____________________.
52. Video – What are the 2 types of batteries?
53. Another word for a battery is a ________.
54. A cell is a single unit that contains ______________.
55. As the chemicals react, _________________ are removed from certain molecules, leaving behind
positively charged ions.
56. The electrons and ions are separated and this charge separation creates a __________________.
57. ________________________ are batteries designed for one time use.
58. ________________________ are batteries that can be recharged.
59. In a rechargeable battery, current is sent through the battery in a reverse direction, which reverses the
direction of the _______________________ and makes the material available again to produce voltage.
60. The voltage output of a battery is measured between two _______________.
61. These terminals are called ________________.
62. One electrode is ________________ and the other is __________________.
63. When connected in a circuit, electrons flow through the circuit from the negative to the ___________.
64. The negative electrode is called a ________________.
65. The positive electrode is called the _____________.
66. Batteries can be added together in ___________ to produce a higher voltage.
67. Adding cells in series means that the ______________________ terminal from one cell is connected to
the negative terminal of another battery.
68. In a series circuit, there is only _______ path for current.
69. In a parallel circuit, there are ______________________ paths for the current to flow.
70. Shorthand symbols:
1. Battery - ____________
2. Light bulb - __________
3. Switch - ____________
4. Conductors - __________
71. Schematic of a simple circuit:
72. An AC voltage source reverses the positive and negative terminals many times per second. A majority
of AC circuits cycle at a rate of _________________________. The cycling rate is called the
____________________.
73. Frequency is measured in cycles per second, or _______________.