Module 04 Electronic 100 Important Sentences for Revision

1. Basics of Electronics

1. Electronics deals with the flow of electrons in vacuum, gas, or semiconductor.
2. Current flow in electronics is controlled using components.
3. Electric current is the movement of free electrons in a circuit.
4. Voltage is the potential difference that drives current.
5. Resistance limits the amount of current in a circuit.
6. Conductors allow easy flow of electrons.
7. Insulators resist the flow of electrons.
8. Semiconductors have conductivity between conductors and insulators.
9. Silicon and germanium are common semiconductor materials.
10. Doping adds impurities to semiconductor to change its properties.

2. Types of Current

11. Direct current (DC) flows in one direction only.
12. Alternating current (AC) changes direction periodically.
13. DC voltage is constant over time.
14. AC voltage varies sinusoidally with time.
15. Frequency is the number of AC cycles per second.
16. Frequency is measured in hertz (Hz).
17. Period is the time taken for one complete AC cycle.
18. The RMS value of AC gives equivalent DC value.
19. Peak value is the maximum value of an AC waveform.
20. Average value of AC equals 0.637 × peak value.

3. Conductors, Resistors, and Materials

21. Ohm’s law states V = I × R.
22. Resistance increases with temperature in most metals.
23. Resistivity depends on material type and temperature.
24. Conductivity is the reciprocal of resistivity.
25. Colour codes identify resistor values.
26. Fixed resistors have constant resistance.
27. Variable resistors allow resistance adjustment.
28. Potentiometers act as voltage dividers.
29. Thermistors change resistance with temperature.
30. LDRs (Light Dependent Resistors) change resistance with light intensity.

4. Capacitors

31. Capacitor stores electrical energy in an electric field.
32. Capacitance is the ability to store charge.
33. Unit of capacitance is the farad (F).
34. Capacitance increases with plate area and decreases with plate distance.
35. Dielectric material increases capacitor’s efficiency.
36. Energy stored in a capacitor = ½ C × V².
37. Capacitor blocks DC and allows AC to pass.
38. Electrolytic capacitors are polarized.
39. Ceramic capacitors are non-polarized.
40. Capacitors are used for filtering, timing, and coupling circuits.

5. Inductors

41. Inductor stores energy in a magnetic field.
42. Inductance opposes change in current flow.
43. Unit of inductance is the henry (H).
44. Inductance increases with more coil turns.
45. Inductance increases with iron or ferrite core.
46. Inductive reactance increases with frequency.
47. Formula for inductive reactance: XL = 2πfL.
48. Inductors are used in filters and tuned circuits.
49. Mutual inductance occurs between two nearby coils.
50. Energy stored in inductor = ½ L × I².

6. AC Circuits

51. In resistive circuit, voltage and current are in phase.
52. In inductive circuit, current lags voltage by 90 degrees.
53. In capacitive circuit, current leads voltage by 90 degrees.
54. Impedance (Z) is total opposition to AC current.
55. Impedance combines resistance and reactance.
56. Formula: Z = √(R² + (XL − XC)²).
57. Power factor = cos φ, where φ is phase angle.
58. True power = V × I × cos φ.
59. Apparent power = V × I.
60. Reactive power = V × I × sin φ.

7. Diodes

61. A diode allows current to flow in one direction only.
62. It has an anode and a cathode terminal.
63. P-N junction forms when p-type and n-type materials join.
64. Forward bias allows current to pass through diode.
65. Reverse bias blocks current flow.
66. Silicon diode forward voltage drop is about 0.7 V.
67. Germanium diode forward voltage drop is about 0.3 V.
68. Zener diode operates in reverse breakdown region for voltage regulation.
69. LED emits light when forward biased.
70. Photodiode generates current when exposed to light.

8. Rectifiers and Power Supplies

71. Rectifiers convert AC voltage into DC voltage.
72. Half-wave rectifier uses one diode.
73. Full-wave rectifier uses two or four diodes.
74. Bridge rectifier uses four diodes in bridge configuration.
75. Filter capacitor smooths pulsating DC output.
76. Ripple voltage is unwanted AC variation in DC output.
77. Voltage regulators maintain constant DC output.
78. Linear regulator dissipates excess voltage as heat.
79. Switching regulator uses high-frequency switching for efficiency.
80. Power supply converts and stabilizes electrical power for circuits.

9. Transistors

81. Transistor is a three-terminal semiconductor device.
82. Terminals are emitter, base, and collector.
83. NPN and PNP are two transistor types.
84. Small base current controls large collector current.
85. Transistor acts as amplifier or switch.
86. Current gain (β) = collector current / base current.
87. In common emitter configuration, output is inverted.
88. Biasing sets correct operating point of transistor.
89. Saturation means transistor fully conducts.
90. Cut-off means transistor completely off.

10. Digital Electronics and Logic Gates

91. Digital signals have two states: ON (1) and OFF (0).
92. Analog signals vary continuously.
93. Logic gates perform basic digital operations.
94. AND gate output is 1 only if all inputs are 1.
95. OR gate output is 1 if any input is 1.
96. NOT gate output is opposite of input.
97. NAND gate output is opposite of AND output.
98. NOR gate output is opposite of OR output.
99. XOR gate output is 1 when inputs are different.
100. Digital electronics form the basis of computer and avionics systems.

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Module 01 Mathematics 100 important sentences for Revision

1. Basic Arithmetic

1. Mathematics is the science of numbers and quantities.
2. Addition combines two or more quantities into one.
3. Subtraction finds the difference between two numbers.
4. Multiplication is repeated addition of the same number.
5. Division splits a number into equal parts.
6. The order of operations follows BODMAS rule.
7. BODMAS means Brackets, Orders, Division, Multiplication, Addition, Subtraction.
8. A fraction shows a part of a whole.
9. The numerator is the number above the fraction line.
10. Below the fraction line the number is called denominator.

2. Factions and Decimals

11. Like fractions have the same denominator.
12. Unlike fractions have different denominators.
13. To add fractions, make denominators the same.
14. Improper fractions have numerators larger than denominators.
15. Mixed fractions combine whole numbers and fractions.
16. Decimal numbers are fractions with denominators as powers of ten.
17. To convert a fraction to a decimal, divide numerator by denominator.
18. To convert a decimal to percentage, multiply by 100.
19. 0.75 equals ¾ or 75%.
20. 1/5 equals 0.2 or 20%.

3. Ratios and Proportions

21. A ratio compares two quantities by division.
22. A proportion shows two ratios are equal.
23. Ratios can be simplified like fractions.
24. Direct proportion means both quantities increase together.
25. Inverse proportion means one quantity increases, the other decreases.
26. Example: speed and time are inversely proportional.
27. Example: distance and time are directly proportional.
28. Cross multiplication is used to solve proportions.
29. Percentage = (part ÷ whole) × 100.
30. Ratio 2:3 means for every 2 of one, there are 3 of another.

4. Powers and Roots

31. A power or index shows repeated multiplication.
32. .
33. Any number to power zero equals one.
34. A square is a number multiplied by itself.
35. A number multiplied by itself twice is called cube.
36. Square root is the number that produces a given number when multiplied by itself.
37. Cube root gives a number whose cube equals the original number.
38. .
39. .
40. Indices follow rules of addition and subtraction in powers.

5. Algebra Basics

41. Algebra uses symbols to represent unknown quantities.
42. A variable is a letter that represents a number.
43. A term is a combination of numbers and variables.
44. A coefficient is the number multiplied by a variable.
45. Like terms have the same variable and power.
46. Unlike terms have different variables or powers.
47. Equation is a statement showing two expressions are equal.
48. To solve an equation, isolate the variable.
49. Linear equations have variables raised to power one.
50. Simultaneous equations have two or more unknowns solved together.

 6. Algebraic Operations

51. To expand brackets, multiply each term inside by the outside term.
52. To factorize, take out common terms or use identities.
53. .
54. .
55. .
56. Substitution means replacing variables with actual numbers.
57. Formula rearrangement changes the subject of formula.
58. Transposition moves terms across the equal sign by changing signs.
59. Check solutions by substituting values back in the equation.
60. Quadratic equations have variables squared (power of 2).

7. Geometry – Angles and Triangles

61. knowledge of shapes, sizes, and properties of space is geometry.
62. A line is straight with no thickness.
63. An angle is formed when two lines meet.
64. Angles are measured in degrees (°).
65. Right angle equals 90 degrees.
66. Straight line equals 180 degrees.
67. Full circle equals 360 degrees.
68. Acute angle is less than 90 degrees.
69. The Obtuse angle is greater than 90 but less than 180 degrees.
70. Complementary angles add up to 90 degrees.

8. Triangles and Circles

71. The sum of angles in a triangle is always 180 degrees.
72. An equilateral triangle has all sides equal.
73. An isosceles triangle has two sides equal.
74. A scalene triangle has all sides unequal.
75. Pythagoras theorem: .
76. It applies only to right-angled triangles.
77. Hypotenuse is the side opposite the right angle.
78. Circumference of circle = .
79. Area of circle = .
80. Diameter equals twice the radius.

9. Areas and Volumes

81. The Area of rectangle = length × width.
82. The Area of triangle = ½ × base × height.
83. The Area of parallelogram = base × height.
84. Formula of The Area of trapezium = ½ × (sum of parallel sides) × height.
85. The Volume of cube = side³.
86. The Volume of cuboid = length × width × height.
87. The Volume of cylinder = πr²h.
88. The Volume of cone = ⅓πr²h.
89. The Volume of sphere = 4/3πr³.
90. The Surface area of sphere = 4πr².

10. Trigonometry and Statistics

91. Trigonometry relates angles to sides in a triangle.
92. Sine = opposite ÷ hypotenuse.
93. Cosine = adjacent ÷ hypotenuse.
94. Tangent = opposite ÷ adjacent.
95. .
96. The inverse of sine gives angle from ratio.
97. Graphs visually represent data or equations.
98. Formula of Mean = sum of all values ÷ number of values.
99. Median is the middle value in ordered data.
100. Mode is the value that appears most often.

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Module 2 Physics Final Practice Exam (52 Questions 65 Mints)

 

Module -2 Physics

Final Practice Exam

  

 

1. Which of the following is an example of a Longitudinal Wave?
   1.   Radio Wave
   2.   Sound Wave
   3.   Light Wave
2. In which medium does sound travel the fastest?
   1.   Air
   2.   Steel
   3.   Water
3. Wave length is?
   1.   distance between crests
   2.   distance from trough to crest
   3.   distance between top and bottom
4. Which law states that force equals mass times acceleration?
   1.   Newton’s First Law
   2.   Newton’s Second Law
   3.   Newton’s Third Law
5. The rate of change of velocity is called?
   1.   Speed
   2.   Momentum
   3.   Acceleration
6. The formula for work done is?
   1.   Power × Time
   2.   Mass × Velocity
   3.   Force × Distance
7. The unit of pressure is?
   1.   Joule
   2.   Pascal
   3.   Ampere
8. What is the kinetic energy of an aircraft of mass of 2 metric tonnes and has a velocity of 2m/s?
   1.   2 kJ
   2.   8 kJ
   3.   4 kJ
9. The number of radians in a semi circle are ?
   1.   π
   2.   2π
   3.   exactly 3
10. Which device is used to measure atmospheric pressure?
    1.   Hygrometer
    2.   Manometer
    3.   Barometer
11. When the temperature of a gas increases at constant volume, pressure?
    1.   Increases
    2.   Decreases
    3.   Remains constant
12. The SI unit of heat energy is?
    
    1.   Watt
    2.   Calorie
    3.   Joule
13. Heat transfer through solids mainly occurs by?
    
    1.   Convection
    2.   Conduction
    3.   Radiation
14. The speed of sound is highest in ?
    1.   Liquids
    2.   Solids
    3.   Gases
15. Which color has the shortest wave length?
    1.   Violet
    2.   Green
    3.   Red
16. Which instrument measures relative humidity?
    1.   Thermometer
    2.   Barometer
    3.   Hygrometer
17. Which gas law states that volume is directly proportional to temperature?
    1.   Boyle’s Law
    2.   Charles’s Law
    3.   Avogadro’s Law
18. Regenerators are used in fibre optic systems to reduce?
    
    1.   attenuation
    2.   dispersion
    3.   random emission
19. The density of water is approximately?
    
    1.   0.1 g/cm³
    2.   10 g/cm³
    3.   1 g/cm³
20. Heat transmission by convection is confined to?
    
    1.   solids and liquids
    2.   gases and solids
    3.   liquids and gases
21. The Steam Point of water is?
    
    1.   0 Kelvin
    2.   273 Kelvin
    3.   373 Kelvin
22. A material capable of going direct from solid to gas is a ?
    
    1.   Substrate
    2.   Substance
    3.   Sublimate
23. A compressor increases ?
    1.   potential energy
    2.   moving energy
    3.   kinetic energy
24. A process where temperature remains the same is known as?
    1.   isobaric
    2.   isothermic
    3.   isochoric
25. The instrument used to measure force is called ?
    1.   Spring balance
    2.   Thermometer
    3.   Barometer
26. A body moving in a circular path is said to have ?
    1.   Uniform motion
    2.   Centripetal acceleration
    3.   Linear velocity
27. The product of mass and velocity is ?
    1.   Energy
    2.   Acceleration
    3.   Momentum
28. Which device converts chemical energy into electrical energy?
    1.   Motor
    2.   Battery
    3.   Generator
29. The SI unit of momentum is?
    1.   J/s
    2.   N·m
    3.   kg·m/s
30. Which of the following has maximum inertia?
    1.   A car
    2.   A truck
    3.   A bicycle
31. The force which opposes twisting deformation is?
    1.   torsion
    2.   strain
    3.   shear
32. A millilitre is equal to ?
    1.   one million litres
    2.   one millionth of a litre
    3.   one thousandth of a litre
33. The gyroscopic principle is based upon?
    1.   Newton’s 2nd Law
    2.   Newton’s 1st Law
    3.   Newton’s 3rd Law
34. The SI unit of density is the?
    1.   kilogram per cubic metre (kg/m3)
    2.   Pascal (Pa)
    3.   cubic metre (m3)
35. Convert 220 gallons to litres?
    1.   1000 litres
    2.   48.4 litres
    3.   500 litres
36. How much lift is produced on a wing can be derived from?
    1.   Charles law
    2.   Faraday's law
    3.   Bernoulli's Theorem
37. A good refrigerant has?
    1.   high condensing pressure, high evaporating temperature
    2.   low condensing pressure, low vaporating temperature
    3.   high condensing pressure, low evaporating temperature
38. Boyle's law states that?
    1.   pressure equals temperature divided by volume
    2.   pressure varies directly with volume
    3.   pressure varies inversely with volume
39. 10 BTU is equivalent to?
    1.   63,560 Joules
    2.   10,550 Joules
    3.   570 Joules
40. A wave in which the vibrations are parallel to, or along, the direction of travel is a?
    1.   Upright Wave
    2.   Longitudinal Wave
    3.   Transverse Wave
41. Increasing the Amplitude of a sound wave increases its?
    1.   moment
    2.   loudness
    3.   pitch
42. Quality of sound is dependant on?
    1.   medium it is traveling through
    2.   number and pitch of harmonics
    3.   frequency of the supply
43. The speed of sound in air at 0 °C is approximately?
    1.   181 m/s
    2.   3 * 108 m/s
    3.   331 m/s
44. A Concave mirror is used in?
    1.   headlights
    2.   a periscope
    3.   a rear view mirror
45. The light gathering power of a lens is indicated by its?
    1.   material
    2.   focal ratio
    3.   thickness of the lens
46. Lasers use which source of light?
    1.   Coherent
    2.   Refraction
    3.   Scattered
47. The power of a lens is measured in?
    1.   Lumens per Watt
    2.   Watts
    3.   Diopters
48. The refractive index for air is approximately?
    1.   10
    2.   1
    3.   0
49. The power of a lens is calculated from the?
    1.   focal length squared
    2.   product of the focal length and its distance from the pole
    3.   reciprocal of the focal length
50. The fibre optic receiver is a?
    1.   photodiode
    2.   laser diode
    3.   light emitting diode
51. What will the image produced through a divergent lens be?
    1.   Negative
    2.   Real
    3.   Virtual
52. Temperature is a measure of ?
    1.   the amount of vibration of molecules
    2.   the heat energy of particles
    3.   the amount of friction produced by two mating surfaces

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