Neets Module 1

Front 1

Q1. What is matter, and in what three states is it found?

Back 1

A1. Anything that occupies space and has weight. Solids, liquids, gases.

Front 2

Q2. What is an element?

Back 2

A2. A substance which cannot be reduced to a simpler substance by chemical means.

Front 3

Q3. What is a compound?

Back 3

A3. A substance consisting of two or more elements.

Front 4

Q4. What is the difference between a compound and a mixture?

Back 4

A4. A compound is a chemical combination of elements that cannot be separated by physical means. A
mixture is a physical combination of elements and compounds that are not chemically combined.

Front 5

Q5. What is a molecule?

Back 5

A5. A chemical combination of two or more atoms.

Front 6

Q6. What are the three types of subatomic particles, and what are their charges?

Back 6

A6. Electrons-negative, protons-positive, and neutrons-neutral.

Front 7

Q7. What is energy of motion called?

Back 7

A7. Kinetic energy.

Front 8

Q8. How is invisible light changed to visible light in a fluorescent light?

Back 8

A8. Invisible light photons (ultraviolet) bombard the phosphor atom in the light tube. The phosphor
atoms emit visible light photons.

Front 9

Q9. What determines the valence of an atom?

Back 9

A9. The number of electrons in the outer shell.

Front 10

Q10. What is an ion?

Back 10

A10. An atom with more or less than its normal number of electrons.

Front 11

Q11. What determines whether a substance is a conductor or an insulator?

Back 11

A11. The number of valence electrons.

Front 12

Q12. How is a negative charge created in a neutral body?

Back 12

A12. Through the accumulation of excess electrons.

Front 13

Q13. How are static charges created?

Back 13

A13. By friction.

Front 14

Q14. What is the electrical charge of an atom which contains 8 protons and 11 electrons?

Back 14

A14. Negative.

Front 15

Q15. What is the relationship between charged bodies?

Back 15

A15. Like charges repel, and unlike charges attract with a force directly proportional to the product of
their charges and inversely proportional to the square of the distance between them.

Front 16

Q16. What is an electrostatic field?

Back 16

A16. The space between and around charged bodies.

Front 17

Q17. In what direction are electrostatic lines of force drawn?

Back 17

A17. Leaving positive, entering negative.

Front 18

Q18. What are some examples of electrical equipment which use magnetism?

Back 18

A18. Motors, generators, speakers, computers, televisions, tape recorders, and many others.

Front 19

Q19. What are magnetic materials?

Back 19

A19. Those materials that are attracted by magnets and have the ability to become magnetized.

Front 20

Q20. What characteristics do all ferromagnetic materials have in common?

Back 20

A20. The relative ease with which they are magnetized.

Front 21

Q21. What type of magnetic material should be used to make a temporary magnet?

Back 21

A21. A material that exhibits low reluctance and high permeability, such as iron or soft steel.

Front 22

Q22. What is retentivity?

Back 22

A22. The ability of a material to retain magnetism.

Front 23

Q23. How does the law of magnetic poles relate to the law of electric charges?

Back 23

A23. They are very similar; like charges repel, unlike charges attract, like poles repel —unlike poles
attract.

Front 24

Q24. A compass is located at the geographical North Pole. In which direction would its needle point?

Back 24

A24. To the magnetic north pole.

Front 25

Q25. Using Weber’s molecular theory of magnetism, describe the polarity of the magnetic poles
produced by stroking a magnetic material from right to left with the south pole of a magnet.

Back 25

A25. South pole at the right, north pole at the left.

Front 26

Q26. What is the difference between the domain theory and Weber’s theory of magnetism?

Back 26

A26. The domain theory is based upon the electron spin principle; Weber’s theory uses the concept of
tiny molecular magnets.

Front 27

Q27. Refer to figure 1-13. For what purpose would you sprinkle iron filings on the glass plate?

Back 27

A27. To enable you to "see" the magnetic field.

Front 28

Q28. Refer to figure 1-13. What pattern would be formed if sawdust was sprinkled on the glass instead
of iron filings?

Back 28

A28. No specific pattern, sawdust is a nonmagnetic material.

Front 29

Q29. What is a magnetic line of force?

Back 29

A29. An imaginary line used to illustrate magnetic effects.

Front 30

Q30. In what way do magnetic lines of force differ from electrostatic lines of force?

Back 30

A30. Electrostatic lines of force do not form closed loops.

Front 31

Q31. How should a delicate instrument be protected from a magnetic field?

Back 31

A31. By shielding or surrounding the instrument with a soft iron case, called a magnetic shield or
screen.

Front 32

Q32. How should bar magnets be stored?

Back 32

A32. In pairs, with opposite poles together to provide a complete path for magnetic flux.

Front 33

Q33. What is the definition of energy?

Back 33

A33. The ability to do work.

Front 34

Q34. What type of energy does a rolling stone have?

Back 34

A34. Kinetic energy.

Front 35

Q35. What kind of energy does the stone have if it is at rest at the top of a hill?

Back 35

A35. Potential energy.

Front 36

Q36. What term describes voltage or emf?

Back 36

A36. Difference of potential.

Front 37

Q37. Convert 2.1 kV to volts.

Back 37

A37. 2100 volts.

Front 38

Q38. Express the following in more simple terms. (a) 250,000 volts, (b) 25,000,000 microvolts, (c)
0.001 millivolt.

Back 38

A38. (a) 250 kV, (b) 25 V, (c) 1 9

Front 39

Q39. A device which supplies a voltage is commonly referred to by what name?

Back 39

A39. A voltage source.

Front 40

Q40. Name the six methods of producing a voltage.

Back 40

A40. Friction, pressure, heat, light, chemical action, and magnetism.

Front 41

Q41. The piezoelectric effect is an example of a voltage being produced by what method?

Back 41

A41. Pressure.

Front 42

Q42. A thermocouple is a device that produces voltage by what method?

Back 42

A42. Heat.

Front 43

Q43. A battery uses what method to produce a voltage?

Back 43

A43. Chemical.

Front 44

Q44. A generator uses what method to produce a voltage?

Back 44

A44. Magnetic.

Front 45

Q45. According to electron theory, an electric current flows from what potential to what potential?

Back 45

A45. Electron theory assumes that electron flow is from negative to positive.

Front 46

Q46. The effects of directed drift take place at what rate of speed?

Back 46

A46. The speed of light (186,000 miles per second, 300,000,000 meters per second).

Front 47

Q47. What is the relationship of current to voltage in a circuit?

Back 47

A47. Current increases as voltage increases

Front 48

Q48. Convert 350 mA to amperes.

Back 48

A48. 0.35 amperes.

Front 49

Q49. What is the symbol for ohm?

Back 49

A49.Upside down horseshoe

Front 50

Q50. When would silver be used as a conductor in preference to copper?

Back 50

A50. When the need for conductivity is great enough to justify the additional expense.

Front 51

Q51. Which wire has the least resistance? Wire A-copper, 1000 circular mils, 6 inches long. Wire
B-copper, 2000 circular mils, 11 inches long.

Back 51

A51. Wire B.

Front 52

Q52. Which temperature coefficient indicates a material whose resistance increases as temperature
increases?

Back 52

A52. Positive.

Front 53

Q53. What term describes a material whose resistance remains relatively constant with changes in
temperature?

Back 53

A53. Zero temperature coefficient.

Front 54

Q54. What is the unit of conductance and what other term is sometimes used?

Back 54

A54. The mho (v), siemens.

Front 55

Q55. What is the relationship between conductance and resistance?

Back 55

A55. They are reciprocals of each other.

Front 56

Q56. What is schematic symbol for a resistor?

Back 56

A56.

Front 57

Q57. What does the wattage rating of a resistor indicate?

Back 57

A57. Its ability to dissipate heat.

Front 58

Q58. What are the two disadvantages of carbon-type resistors?

Back 58

A58. 1. Change value with age. 2. Limited power capacity

Front 59

Q59. What type resistor should be used to overcome the disadvantages of the carbon resistor?

Back 59

A59. The wirewound resistor.

Front 60

Q60. Describe the differences between the rheostat connections and those of the potentiometer.

Back 60

A60. The rheostat may have two connections, one fixed and one moveable; the potentiometer always has
three connections, one moveable and two fixed.

Front 61

Q61. Which type of variable resistor should you select for controlling a large amount of current?

Back 61

A61. The rheostat.

Front 62

Q62. A carbon resistor has a resistance of 50 ohms, and a tolerance of 5 percent. What are the colors of
bands one, two, three, and four, respectively?

Back 62

A62. The bands are green, black, black, and gold.

Front 63

Q63. A carbon resistor has the following color bands: The first band is yellow, followed by violet,
yellow, and silver. What is the ohmic value of the resistor?

Back 63

A63. 470,000 ohms (470 kilohms).

Front 64

Q64. The same resistor mentioned in question 63 has a yellow fifth band. What does this signify?

Back 64

A64. The resistor’s chance of failure is 0.001 percent for 1000 hours of operation.

Front 65

Q65. A resistor is handed to you for identification with the following color code: the first band is blue,
followed by gray, green, gold, and brown. What is the resistor’s value?

Back 65

A65. 6,800,000 ohms (6.8 megohms), with 5% tolerance, and a 1% reliability level.