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MODULE 3 CHAPTER 5 QUIZ 6

Question Number. 51. If the insulation resistance of a lead/acid battery is down, it indicates.  Option A. case leakage.  Option B. leakage between positive and negative terminals.  Option C. intercell leakage.  Correct Answer is. case leakage.  Explanation. NIL ................................. .Question Number. 52. When the battery is connected to the aircraft, which terminal should you connect first?.  Option A. Any. Option B. Positive. Option C. Negative. Correct Answer is. Positive. Explanation. Aircraft Electricity and Electronics Eismin Page 43 ................................ ..Question Number. 53. An ammeter in a battery charging system is for the purpose of indicating the.  Option A. rate of current used to charge the battery. Option B. amperage available for use.  Option C. total amperes being used in the aeroplane. Correct Answer is. rate of current used to charge the battery. Explanation. Whilst charging (as the question says) the ammeter shows current flow TO the bat

MODULE 3 CHAPTER 5 QUIZ 5

Question Number. 41. A ni-cad battery found to be below normal capacity should.  Option A. have its electrolyte adjusted.  Option B. be removed and used for ground use only.  Option C. be re-charged with a freshening charge.  Correct Answer is. be re-charged with a freshening charge.  Explanation. See Jeppesen's Aircraft Batteries ..................................  Question Number. 42. In cold weather, to prevent the electrolyte freezing, a battery must be kept. Option A. fully charged. Option B. does not matter. Option C. fully discharged. Correct Answer is. fully charged. Explanation. Checkout www.amplepower.com/primer/winter/ ..................................  Question Number. 43. The internal resistance of a battery off load compared to on load is. Option A. the same.  Option B. increased. Option C. decreased. Correct Answer is. the same. Explanation. Internal resistance is constant, regardless of load ..................................  Question Number. 44. Two 12V, 40Ah cel

MODULE 3 CHAPTER 5 QUIZ 4

Question Number. 31. The Daniel Cell electrodes are. Option A. copper and zinc. Option B. carbon and zinc. Option C. zinc and manganese dioxide. Correct Answer is. copper and zinc. Explanation. The Daniel Cell was an improvement on the first ever cell made by Voltaire. Both used copper and zinc electrodes .................................. Question Number. 32. In a thermocouple, where is voltage measured?. Option A. At both junctions. Option B. At the hot junction. Option C. At the cold junction. Correct Answer is. At the cold junction. Explanation. The voltmeter measures the voltmeter across the cold junction of a thermocouple .................................. Question Number. 33. Mercury cells are covered with a metal cover. Option A. as a protective cover. Option B. as a negative terminal. Option C. as a positive terminal. Correct Answer is. as a positive terminal. Explanation. The outer cover (or case) of a mercury cell is the positive terminal - Have a look at your watch or calcu

MODULE 3 CHAPTER 5 QUIZ 3

Question Number. 21. If a nicad battery is not to be used immediately it should be stored. Option A. dry. Option B. fully charged. Option C. fully dissipated. Correct Answer is. fully dissipated. Explanation. Ni-cad batteries must be stored fully discharged. Often with a metal bar across their terminals to ensure they are fully dissipated .................................. Question Number. 22. In a mercury cell the steel casing is. Option A. the negative terminal. Option B. neither. Option C. the positive terminal. Correct Answer is. the positive terminal. Explanation. The 'outer can' is in contact with the zinc anode, which is positive .................................. Question Number. 23. To improve the life of a dry cell it would be manufactured with. Option A. more electrolyte paste. Option B. more zinc. Option C. a pure carbon positive rod. Correct Answer is. more zinc. Explanation. The zinc (negative electrode or cathode) gets eaten away .................................

MODULE 3 CHAPTER 5 QUIZ 2

Question Number. 11. Two batteries 12V and 40 Ah each, are in series. What is the total capacity?. Option A. 12V 80 Ah. Option B. 24V 40 Ah. Option C. 24V 80Ah. Correct Answer is. 24V 40 Ah. Explanation. Batteries in series - voltage increases but capacity remains the same (vice versa if they were in parallel) .................................. Question Number. 12. If a battery has got low internal resistance, then the. Option A. no load voltage will be the same as on load voltage. Option B. on load voltage will be greater than no load voltage. Option C. no load voltage will be greater than on load voltage. Correct Answer is. no load voltage will be greater than on load voltage. Explanation. The internal resistance will always drop the voltage and reduce the terminal voltage. It is the same whether it is high or low internal resistance - just a matter of 'how much' .................................. Question Number. 13. Conventional current flow inside a battery is from. Option

MODULE 3 CHAPTER5 QUIZ 1

05.DC Sources of Electricity .................................. Question Number. 1. A 20 cell battery with each cell having an internal resistance of 0.1 ohms is charged with 2 leads having a total resistance of 0.1 ohms. The battery is charged with a current of 5 amps. What is the charging voltage ?. Option A. 0.5 volts. Option B. 10.5 volts. Option C. 0.005 volts. Correct Answer is. 10.5 volts. Explanation. Total battery internal resistance = 0.1 * 20 = 2 ohms, Total circuit resistance, including leads = 2 + 0.1 = 2.1 ohms, V = I * R = 5A * 2.1 ohms = 10.5V .................................. Question Number. 2. Two 10V, 20 Ah batteries are connected in parallel and connected across a 10 ohm load. How long could they supply normal current before the voltage begins to decay?. Option A. 40 hours. Option B. 20 hours. Option C. 4 hours. Correct Answer is. 40 hours. Explanation. Use Ohms law to work out the current (1A). Two batteries in parallel then rating is doubled (40 Ah) ........

MODULE 3 CHAPTER 4 QUIZ 1

Generation of Electricity .................................. Question Number. 1. Thermocouple harnesses are made from the same materials as the thermocouple so that. Option A. mini junctions are not formed. Option B. the resistance is not increased beyond limits. Option C. they will not corrode. Correct Answer is. mini junctions are not formed. Explanation. NIL .................................. Question Number. 2. Point A on the armature of the generator shown is producing. Option A. minimum current. Option B. zero current. Option C. maximum current. Correct Answer is. maximum current. Explanation. NIL .................................. Question Number. 3. A piezoelectric device generates electricity through. Option A. friction. Option B. light. Option C. pressure. Correct Answer is. pressure. Explanation. NIL ................................. .Question Number. 4. A photozoidal cell produces electricity when subjected to. Option A. light. Option B. pressure. Option C. heat. Corr

MODULE 3 CHAPTERR 3 QUIZ 5

Question Number. 41. The unit of energy is the. Option A. Joule. Option B. Watt. Option C. Coulomb. Correct Answer is. Joule. Explanation. Energy is measured in Joules .................................. Question Number. 42. Potential difference is another term for. Option A. voltage . Option B. charge. Option C. energy. ... Correct Answer is. voltage. Explanation. Potential difference, electromotive force, electrical pressure, are all terms for voltage .................................. Question Number. 43. XL is the symbol of. Option A. inductive reactance. Option B. capacitive reactance. Option C. impedance. Correct Answer is. inductive reactance . Explanation. 'L' is for inductance, 'X' is for reactance .................................. Question Number. 44. Using Ohm's law. Option A. current is directly proportional to the resistance. Option B. current is directly proportional to the EMF. Option C. resistance is directly proportional to EMF . Correct A

MODULE 3 CHAPTER 3 QUIZ 4

Question Number. 31. The property of a material to accept lines of flux is called. Option A. retentivity. Option B. reluctance. Option C. permeability. Correct Answer is. permeability. Explanation. NIL ................................. .Question Number. 32. Magnetomotive force can be found by. Option A. I * N. Option B. Blv. Option C. N/I. Correct Answer is. I * N. Explanation. MMF (symbol H) = amps * turns (units are ampere turns) .................................. Question Number. 33. When a conductor is cut by magnetic lines of force an EMF is induced. This is. Option A. Kirkchoff's Law. Option B. Faraday's Law. Option C. Lenz's Law. Correct Answer is. Faraday's Law. Explanation. Faraday's Law is induced EMF is directly proportional to the rate of change of flux .................................. Question Number. 34. The direction of induced conventional current in a wire rotating in a magnetic field can be determined by. Option A. cork screw rule. Option B. Fl

MODULE 3 CHAPTER 3 QUIZ 2

Question Number. 11. A volt can be considered to be a. Option A. unit of electrical power. Option B ..................................Quantity of electrical energy. Option C. unit of electrical pressure. Correct Answer is. unit of electrical pressure. Explanation. Electrical pressure' is sometimes used instead of voltage, due to its analogy to a head of pressure in fluids .................................. Question Number. 12. What is 3.25 volts in millivolts?. Option A. 3,250 millivolts. Option B. 325,000 millivolts. Option C. 3.25 millivolts. Correct Answer is. 3,250 millivolts. Explanation. NIL .................................. Question Number. 13. Electromotive force is measured in. Option A. Watts. Option B. Ohms. Option C. Volts. Correct Answer is. Volts. Explanation. EMF is another term for voltage, or potential difference (PD) or electrical pressure, all measured in Volts ................................. .Question Number. 14. Kirchhoff's law states. Option A. the al

MODULE 3 CHAPTER 3 QUIZ 3

Question Number. 21. A shunt is used with. Option A. an ammeter. Option B. a voltmeter. Option C. an ohmmeter. Correct Answer is. an ammeter. Explanation. A shunt is used to change the working range of an ammeter, by 'shunting' around the ammeter, a major portion of the current being measured .................................. Question Number. 22. If a load in series has a current passing through it, the magnetic field can be worked out by using. Option A. the corkscrew rule. Option B. left hand rule. Option C. right hand rule. Correct Answer is. the corkscrew rule. Explanation. NIL .................................. Question Number. 23. The unit for power is. Option A. Joules per second. Option B. N/m. Option C. Volts/Amps. Correct Answer is. Joules per second. Explanation. Power = energy (joules) / time (seconds) .................................. Question Number. 24. In conventional flow, the left hand rule applies to. Option A. generators. Option B. batteries. Option C

MODULE 3 CHAPTERR 3 QUIZ 1

03. Electrical Terminology .................................. Question Number. 1. If a photon radiating into an electronic device causes the production of an electron/hole pair, the device is known as a. Option A. light emitting diode. Option B. laser diode. Option C. photodiode. Correct Answer is. photodiode. Explanation. NIL .................................. Question Number. 2. Faraday's Law States that. Option A. the magnitude of the EMF is indirectly proportional to the rate of change of flux. Option B. the magnitude of the EMF is directly proportional to the magnetic flux. Option C. the magnitude of the EMF is directly proportional to the rate of change of flux. Correct Answer is. the magnitude of the EMF is directly proportional to the rate of change of flux. Explanation. NIL .................................. Question Number. 3. Which of the following is 1 Amp?. Option A. 1000 mA. ... Option B. 1000 kA. Option C. 1000 μA. Correct Answer is. 1000 mA. Explanation. NIL .

MODULE 3 CHAPTER 2 QUIZ 2

Question Number. 11. The resistance of the current return path through the aircraft is always considered negligible, provided the. Option A. structure is adequately bonded. Option B. voltage drop across the circuit is checked. Option C. generator is properly grounded. Correct Answer is. structure is adequately bonded. Explanation. NIL .................................. Question Number. 12. If an insulated conductor is placed near to a negatively charged rod, the nearest end of the conductor becomes. Option A. No change will occur . Option B. negatively charged. Option C. positively charged. Correct Answer is. positively charged. Explanation. The free electrons in the conductor will be repelled away from the rod, leaving that end positively charged .................................. Question Number. 13. The electromagnetic force between two charged bodies is. Option A. inversely proportional to the distance between them. Option B. inversely proportional to the square of the dist

MODULE 3 CHAPTER 2 QUIZ 1

02. Static Electricity and Conduction. Question Number. 1. A semi-conductor will have. Option A. two electrons in the outer shell . Option B. four electrons in the outer shell.   Option C. eight electrons in the outer shell. Correct Answer is. four electrons in the outer shell. Explanation. NIL. Question Number. 2. Ion current is found in. Option A. conductors and semi-conductors.   Option B. liquids and gasses.   Option C. semi-conductors.   Correct Answer is. liquids and gasses. Explanation. NIL. Question Number. 3. Electricity conducts through.   Option A. vacuum. Option B. solids and liquids only. Option C. solids only. Correct Answer is. solids and liquids only. Explanation. Electricity can conduct through a vacuum by thermionic emmission. Question Number. 4. An example of a good electrical insulator is. Option A. aluminium.   Option B. glass. Option C. mercury. Correct Answer is. glass. Explanation. You MUST know that surely!. Question Number. 5. Static charges remaining in an ai

MODULE 3 PART 1.5

Question Number. 41. Surface molecular attraction between two different molecules is. Option A. adhesive. Option B. gravitational. Option C. cohesive. Correct Answer is. adhesive. Explanation. Cohesion is the property that causes like substances to cling together (e.g. water molecules, forming raindrops - from 'cohesion' meaning to stick together). Adhesion is the property that causes unlike substances to stick together (e.g. the raindrops stick, or 'adhere to' a washing line). Question Number. 42. The atomic mass number is the number of. Option A. protons plus electrons. Option B. neutrons plus electrons. Option C. protons plus neutrons. Correct Answer is. protons plus neutrons. Explanation. Mass Number is the number of protons + neutrons. Question Number. 43. A catalyst in a chemical reaction does what?. Option A. Can either speed it up or slow it down. Option B. Speeds it up. Option C. Slows it down. Correct Answer is. Speeds it up. Explanation. Official definition o

MODULE 3 PART 1.3

Question Number. 21. What form of heat is used to turn a solid into a liquid?. Option A. specific heat. Option B. coefficient of heat. Option C. heat of fusion. Correct Answer is. heat of fusion. Explanation. Fusion' is another term for melting (as in fusion welding). Question Number. 22. Change from solid to gas state without going through liquid state is called. Option A. transformation. Option B. sublimation. Option C. state leap. Correct Answer is. sublimation. Explanation. Sublimation is when a solid vapourises without first melting. Question Number. 23. What is the smallest particle of matter that can exist in nature?. Option A. A molecule. Option B. An isotope. Option C. An atom. Correct Answer is. An atom. Explanation. An atom is the smallest particle of matter that can exist in nature. Question Number. 24. A positive ion. Option A. has extra electrons. Option B. has missing electrons. Option C. is a radioactive isotope. Correct Answer is. has missing electrons. Explanation

MODULE 3 PART 1.4

Question Number. 31. A valance electron is an electron. Option A. in the innermost shell. Option B. in the outermost shell. Option C. which is not within an atom. Correct Answer is. in the outermost shell. Explanation. The outer shell is the valence shell. Question Number. 32. Molecules of unlike atoms are combined by their. Option A. adhesive force. Option B. magnetic force. Option C. cohesive force. Correct Answer is. adhesive force. Explanation. Cohesion is the property that causes like substances to cling together (eg water molecules, forming raindrops - from 'cohesion' meaning to stick together). Adhesion is the property that causes unlike substances to stick together (eg the raindrops stick, or 'adhere to' a washing line). Question Number. 33. What is the difference between hydrogen, deuterium and tritium?. Option A. The number of electrons. Option B. The number of protons. Option C. The number of neutrons. Correct Answer is. The number of neutrons. Explanation. T

MODULE 3 PART 1.1

1. Matter. Question Number. 1. An atom with 3 free electrons in its outer shell is said to be. Option A. pentavalent. Option B. covalent. Option C. trivalent. Correct Answer is. trivalent. Explanation. Number of electrons in the outer shell is called the valency - 1 = monovalent, 2 = divalent, 3 = trivalent etc. Question Number. 2. What is the mass number of an element?. Option A. Number of electrons and protons. Option B. Number of neutrons and protons. Option C. Number of electrons and neutrons. Correct Answer is. Number of neutrons and protons. Explanation. NIL. Question Number. 3. What do you get when you add 2H2 and O?. Option A. H2 O. Option B. 2H2 O. Option C. 2H2 O2 . Correct Answer is. 2H2 O. Explanation. Water is molecules each made up of 2 hydrogen atoms and 1 oxygen atom. Here ther is 4 hydrogen atoms, and 2 oxygen atoms, so we can make 2 water molecules. Question Number. 4. The splitting of a chemical compound is called. Option A. bombardment. Option B. synthesis. Option C

MODULE 3 PART 1.2

Question Number. 11. If the outer shell of an atom is full the the element is. Option A. unstable / reactive. Option B. a good conductor. Option C. practically inert. Correct Answer is. practically inert. Explanation. NIL. Question Number. 12. Molecules of the same compound are held together by. Option A. cohesive forces. Option B. adhesive forces. Option C. gravitational forces. Correct Answer is. cohesive forces. Explanation. Cohesion is the property that causes like substances to cling together (eg water molecules, forming raindrops). Adhesion is the property that causes unlike substances to stick together (eg the raindrops stick on a washing line). Question Number. 13. Oxygen has a valency of. Option A. 2. Option B. 6. Option C. 8. Correct Answer is. 2. Explanation. Oxygen has 6 electrons in its outer shell. The valency is the number of electrons in the outer shell if that number is 4 or less. If there are more than 4 electrons, the valency is 8 minus the number of electrons. In th

Logic gates

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Logic gates (AND, OR, XOR, NOT, NAND, NOR and XNOR) A logic gate is an elementary building block of a digital circuit. Most logic gates have two inputs and one output. At any given moment, every terminal is in one of the two binaryconditions low (0) or high (1), represented by different voltage levels. The logic state of a terminal can, and generally does, change often, as the circuit processes data. In most logic gates, the low state is approximately zero volts (0 V), while the high state is approximately five volts positive (+5 V). There are seven basic logic gates: AND, OR, XOR, NOT, NAND, NOR, and XNOR. The AND gate is so named because, if 0 is called "false" and 1 is called "true," the gate acts in the same way as the logical "and" operator. The following illustration and table show the circuit symbol and logic combinations for an AND gate. (In the symbol, the input terminals are at left and the output terminal is at right.) The output is "true&q