easa modules questions

A zener diode is used for a) rectification Ans b) voltage stabilization c) modulation * A multi-layer PCB has Ans a) one layer on either side b) two or more layers on one or both sides c) two or more layers connected in series * When a servomotor overshoots after a step input and oscillates it is a) over damped Ans b) under damped c) critically damped * The rotor of a desynn indicator is a) an electromagnet Ans b) a permanent magnet c) an AC magnet * The position feedback from a potentiometer is Ans a) anti-phase b) in phase c) 90 degrees out of phase * A differential synchro has Ans a) 3 phase stator, 3 phase rotor b) single phase stator, 2 phase rotor c) 3 phase stator, single phase rotor * When a servomotor has stopped, the rate feedback from a tachogenerator is Ans a) zero b) maximum and in phase c) maximum and anti-phase * A tachogenerator is usually used for Ans a) rate feedback b) angular feedback c) position feedback * What is this circuit? Ans a) Half wave rectifier b) Full wa...

An amplifier can provide both voltage gain and current gain when it is connected in the a) common base configuration Ans b) common emitter configuration c) common collector configuration * How do you increase voltage gain of an amplifier? a) decrease base circuit bias Ans b) decrease input resistance c) increase input resistance * In a resolver synchro the stator windings are electrically displaced by Ans a) 90o b) 120o c) 180o * A servo system may include a brake, an automatic trim system is one example where a brake is used. The brake is a) applied during trimming to prevent oscillations about the demand position Ans b) applied when trimming is complete to prevent stabilizer creep c) applied during trimming to prevent servo runaway * What gives the colour of an LED? a) The plastic it is encased in Ans b) The active element c) The type of gas used inside it * A germanium diode is used for Ans a) rectification b) voltage stabilization c) modulation * Why is a diode put in parallel with...

The position feedback signal is a) in phase with the input demand signal Ans b) in anti-phase with the demand signal c) phase advanced by 90o with respect to the input signal * A servo system that overshoots and oscillates is Ans a) under damped b) over damped c) critically damped * The power supply to a torque synchro system is connected to a) the transmitter stator b) the transmitter rotor only Ans c) the transmitter and receiver rotors * If the rotor of the receiver in a torque synchro system was prevented from aligning with the transmitter rotor, then a) the transmitter rotor will turn to align with the receiver rotor b) the receiver will overheat Ans c) a high current will flow in the stator windings * This is a diagram of a a) differentiator Ans b) integrator c) adder * A zener diode Ans a) stabilizes voltage at a predetermined level b) allows current to flow in one direction c) acts like a switch * The common collector amplifier is sometimes called the emitter follower circuit b...

If two of the stator leads are cross connected in a control synchro system, a 25o clockwise rotation of the input rotor would result in the output rotor a) moving 25o clockwise Ans b) moving 25o anticlockwise c) moving 180o to rectify the defect * Damping in a servomechanism is easier to apply if Ans a) the mechanism is light and has low inertia b) the mechanism is heavy and has high inertia c) the mechanism is light and has high inertia * Reverse bias a) lowers the potential barrier Ans b) raises the potential barrier c) greatly increases the majority carrier current * If the electrical connections to the feedback generator in a control synchro system were disconnected, the a) motor would run in the wrong direction b) input signal to the amplifier would reduce Ans c) system would tend to oscillate * An increase in servo amplifier gain a) reduces the speed of the system Ans b) increases system response c) reduces tendency to hunt * In a control synchro the stator current ceases to flow...

Angular displacement of the control coils with respect to the reference coils in a two phase induction motor are a) 0o, 180o Ans b) 90o, 270o c) 90o, 120o * A two phase induction motor used in a servomechanism a) will always require a starter Ans b) is self starting under light loads c) runs with no slip * A servomotor having only a tachogenerator as a feedback device will a) vary its speed with input error voltage Ans b) have a constant speed for any given input voltage c) null out at a position dependant upon input error voltage * A hysteresis servo motor is used in a servomechanism because Ans a) it has good starting characteristics b) good speed/voltage relationship c) low inertia * The null position of a torque synchro system is when Ans a) the TX and TR rotors are parallel to each other b) the TX and TR rotors are 90o to each other c) the TX and TR rotors are 120o to each other * Reversal of two of the stator connections on a torque synchro receiver would cause a) the transmitter...

An LVDT has Ans a) an output winding which is wound in series opposition b) an input winding whose voltage will change with load movement c) an output winding whose voltage and frequency is linear to load angular movement * A diode connected across a relay coil is used to a) allow the coil to energize with only one polarity b) cause a delay in switching on Ans c) dissipate coil spikes on switch off * Differential transmitters are used to a) add or subtract two electrical signals Ans b) add or subtract a mechanical signal to an electrical synchro signal c) increase the operating speed of the synchro receiver * To convert a differential synchro from subtraction to addition you would a) reverse the reference phase supply Ans b) change over two rotor and stator connections c) change over all three stator windings * What is resistor R used for? a) Amplification b) Bias Ans c) Stabilisation * When resolving a Cartesian input to a Polar output a) the inputs are a shaft angle and a voltage b) ...

In the following Boolean algebra statement, which gate is described? F = A + B + C Ans a) Or b) Not c) And * In an E and I signal generator at datum, the voltage on the secondary windings Ans a) are equal and opposite b) is maximum c) is zero * In a synchro resolver, the stator coils are at what angle in relation to one another? a) 45 degrees b) 80 degrees Ans c) 90 degrees * In a synchrotel, the a) rotor is fixed and the stator moves b) rotor and stator is fixed Ans c) stator is fixed and the rotor moves * On a PCB, a decoupling capacitor is used to get rid of transient currents between which points? a) The electronic circuit and the aircraft ground Ans b) Interspaced along the circuit c) The negative rail and the rest of the circuit * What does the circuit shown below do? a) Full wave rectifier b) Voltage doubler Ans c) Half wave rectifier * In an LED, what is used to make the colour? Ans a) the doping material b) The electrons c) The plastic lens cover * An atom with 5 electrons in ...

In velocity feedback the signal is a) in phase Ans b) out of phase c) equal to the error signal * When a hole diffuses from the p region to the n region a) it becomes a minority carrier in the n region b) lowers the potential barrier Ans c) raises the potential barrier * A junction diode Ans a) has one p-n junction b) is similar to a vacuum diode but cannot rectify c) can handle only small currents * The rotor of a magnesyn transmitter is a) a dc electromagnet Ans b) a permanent magnet c) an ac electromagnet * In general the accuracy of a synchro system increases if the a) stator current is high Ans b) stator current is low c) rotor current is high * Torque synchro systems are normally used when the Ans a) mechanical load is low b) mechanical load is high c) system accuracy is of extreme importance * In a resolver synchro the stator windings are electrically disposed by Ans a) 90o b) 120o c) 180o * The induced signal in the output coils of the magnesyn system a) de-saturates the soft i...

In the Boolean algebra statement below, the gate described is F = A.B.C a) Nand b) Nor Ans c) And * With a small amplitude voltage, what type of diode would you use to produce the output waveform? Ans a) shottky b) Gunn c) Zener * An increase in negative feedback to the servo amplifier Ans a) increases amplifier stability b) decreases amplifier stability c) has no effect * How is a push-pull transistor arrangement connected? Ans a) emitter to emitter b) collector to collector c) base to base * Thermal runaway in a transistor is caused by Ans a) excessive heat causing maximum current flow b) excessive heat causing minimum current flow c) low heat causing minimum current flow * A single integrated circuit Op Amp has how many pins? a) 4 b) 7 Ans c) 8 * What is the output of the amplifier shown below? a) 0V b) 3V Ans c) 5V * A thyristor is commonly used for a) voltage regulation b) overvolts regulation Ans c) rectification * A diode which emits photons when conducting is a a) zener b) vara...

The surface area of a cone whose flat is 10 cm and diameter is 8 cm is a) 80 p  Ans. b) 40 p c) 120 p (A + B)4 is (A + B) 2  Ans. a) (A + B) 2 b) A + B c) (A + B) 6 An equilateral triangle has a) 2 equal sides b) no equal sides  Ans. c) 3 equal sides 4 3/8 – 2 1/4 + 1/8 = a) 2 1/8 b) 2 1/2  Ans. c) 2 1/4 11/16 + 5/8 = a) 55/128  Ans. b) 21/16 c) 10/11 Given 43 - x = 21, find the value of x  Ans. a) 43 - 21 b) 43 + 21 c) 43 / 21 ¾ multiplied by 0.82 is equal to a) 1.23  Ans. b) 0.615 c) 2.46 7/6 can be expressed as a) 2.6 b) 1.6  Ans. c) 1.166 The ratio of 6:5 can be expressed as a) 20: 25  Ans. b) 24: 20 c) 10: 16 In a right-angled triangle the other two angles are both 45°. The length of the opposite side can be calculated by  Ans. a) sin 45° x length of the hypotenuse side of the triangle b) cos 45° x length of the adjacent side of the triangle c) sin 45° x length of the adjacent side of the triangle Calculate (+ 3) - (- 4) a) -1 ...

The surface area of a cone whose flat is 10 cm and diameter is 8 cm is a) 80 p  Ans. b) 40 p c) 120 p (A + B)4 is (A + B) 2  Ans. a) (A + B) 2 b) A + B c) (A + B) 6 An equilateral triangle has a) 2 equal sides b) no equal sides  Ans. c) 3 equal sides 4 3/8 – 2 1/4 + 1/8 = a) 2 1/8 b) 2 1/2  Ans. c) 2 1/4 11/16 + 5/8 = a) 55/128  Ans. b) 21/16 c) 10/11 Given 43 - x = 21, find the value of x  Ans. a) 43 - 21 b) 43 + 21 c) 43 / 21 ¾ multiplied by 0.82 is equal to a) 1.23  Ans. b) 0.615 c) 2.46 7/6 can be expressed as a) 2.6 b) 1.6  Ans. c) 1.166 The ratio of 6:5 can be expressed as a) 20: 25  Ans. b) 24: 20 c) 10: 16 In a right-angled triangle the other two angles are both 45°. The length of the opposite side can be calculated by  Ans. a) sin 45° x length of the hypotenuse side of the triangle b) cos 45° x length of the adjacent side of the triangle c) sin 45° x length of the adjacent side of the triangle Calculate (+ 3) - (- 4) a) -1 ...

D in hexadecimal is what number in decimal? a) 8  Ans. B) 13 c) 17 In the following equation what is the y-intercept? 4y = 2x + 8 a) 4  Ans. B) 2 c) 8 Two angles of a triangle are 68 o and 32 o. Therefore the third angle must be a) 63o b) 114o  Ans. c) 80o Solve the following equation to find x 4x + 8y = 64 2x – 8y = 86 a) 5  Ans. b) 25 c) 125 Simplify the following (w + z)(x – y)(y – w) (y – x)(w – y)(w + z)  Ans. a) +1 b) -1 c) 0 101012 + 110012 = a) 462 b) 468  Ans. c) 4610 Which of the following formulae are correct for the triangle shown?  Ans. a) C2 = A2 + B2 b) B2 = C2 + A2 c) A2 = C2 + B2  A rectangle 11cm x 120cm. What is its area in m2 a) 1320 b) 13.2  Ans. c) 0.132  What is 738 in binary coded decimal? a) 111100010 b) 1011100010  Ans. c) 11100111000 If a wheel of radius R revolves ½ a turn, how many radians does it turn through? a) 2p radians  Ans. b) p radians c) 2R2 radians If there are two similar angles in a righ...

A cylinder has a diameter of 20 cm and a length of 20 cm, what is its volume? a) 400cm3 b) 1240cm3  Ans. c) 6200cm3 3 1/8 – 1 1/5 =  Ans. a) 1 37/40 b) 1 3/40 c) 2 3/40 Make m the subject of the formula y = mx + c  Ans. a) y - c x b) y - x c c) y - c x Make x the subject of the formula y = mx + c  Ans. a) y - c m b) y - m c c) y - c m Make c the subject of the formula y = mx + c a) y + mx  Ans. b) y - mx c) mx - y What is the formula for calculating the curved area of a cone? a) p x radius2 x height  Ans. b) p x radius x height c) 2/3 x p x radius x height A triangle with equal angles is called a) isosceles  Ans. b) equilateral c) right angled Two gears are in mesh, one is larger than the other, the smaller gear rotates a) at the same speed b) at a lower speed  Ans. c) at a faster speed Calculate 10 x 23 + 10 x 25 a) 32,008,000 b) 520  Ans. c) 400 In a right angle triangle, the sine of an angle is  Ans. a) opposite divided by hypotenuse ...

(x - 3)(x + 5) = a) x2 - 15  Ans. b) x2 + 2x - 15 c) x2 + 2x (6+2)2 X 2 – (2 X 45) =  Ans. a) 38 b) 218 c) 128 V = (a + b) r2 Find a a) V – r2 – b b) (V – b) / r2  Ans. c) V / r2 - b Give the names of a triangle, which has two sides equal in length and two equal angles. a) Equilateral  Ans. b) Isosceles c) Obtuse 17 degrees 49 minutes and 10 seconds added to 22 degrees 22 minutes and 59 seconds, equal a) 40 degrees 11 minutes and 69 seconds b) 39 degrees 11 minutes and 9 seconds  Ans. c) 40 degrees 12 minutes and 9 seconds the diameter of a cylinder is 200 cm and the height is 20 cm, what is the volume.  Ans. a) 628000 cm3 b) 8000 cm3 c) 62800 cm3 In an equilateral triangle, all of the angles are equal, to  Ans. a) p divided by 3 b) p divided by 2 c) p divided by 4 What is an obtuse angle?  Ans. a) one greater than 90o, but less than 180o b) one less than 90o c) one greater than 180o What is tan Æ when Æ = 90o  Ans. a) + Ve infinity b) 0 c) –...

What is the equation of this line?  Ans. a) x + y = - 2 b) y = 2 - x c) x – y = 2 Solve (a + b)(a - b)  Ans. a) a2 - b2 b) a2 + 2ab - b2 c) a2 + b2 Two gear wheels one with 20 teeth and one with 120 teeth meshed together. The small gear turns one revolution. How far does the large gear move? a) 40o  Ans. b) 60o c) 90o An aircraft flies 1350nm in 2 hrs 15 minutes. What is the average speed? a) 650kts  Ans. b) 600kts c) 850kts The straight line from the center to a circle is known as the a) chord  Ans. b) radius c) diameter Hexadecimal is base a) 2 b) 8  Ans. c) 16 y = mx + c can also be written a) x = y/m - c  Ans. b) x = (y - c)/m c) x = y/(m + c) What is the supplement of 13 degrees 13 minutes 13 seconds? a) 167 degrees 46 minutes 47 seconds  Ans. b) 166 degree 46 minutes 47 seconds c) 266 degrees 87 minutes 87 seconds in a right triangle, sin theta =  Ans. a) opposite divided by hypotenuse b) adjacent divided by hypotenuse c) opposite divid...

Using cosine to find the angle of a triangle, which statement is true?  Ans. a) Adj / hyp b) Opp / adj c) Opp / hyp An input gear of 20 teeth drives an output gear of 120 teeth, if the input rotates one revolution, how much does the output turn?  Ans. a) 60o b) 30o c) 45o What is 30% of 0.01? a) 0.03 b) 0.0003  Ans. c) 0.003 Evaluate 15.4 / 2 – 2(4.6 – 15.7)  Ans. a) 29.9 b) 26.5 c) –14.5 A line to create a segment from the centre of a circle is a a) chord  Ans. b) diameter c) radius How far does a wheel of 7m radius travel in one revolution?  Ans. a) 44m b) 22m c) 14m 2x = 4(x - 3) evaluate a) 0.5 b) 2  Ans. c) 6 A shape with 4 equal sides and one 90° angle is a a) parallelogram b) rhombus  Ans. c) square 12x + 14 = 50 When y = 2, solve x 2y a) 14  Ans. b) 12 c) 11.6 What type of equation is y = x2 + 9x + 14?  Ans. a) Quadratic b) Exponential c) Circular How many radians are in 360o?  Ans. a) 2pi b) 4pi c) 65 100112 =  Ans. a)...

In right-angled triangle the longest side is 20 and the other side is 12. The remaining side is a) 22  Ans. b) 16 c) 10 Solve 15.4/2 - 2(6.2 - 15.6)  Ans. a) 26.5 b) 4.5 c) 11.1 What is angle x a) 120o  Ans. b) 60o c) 30o Calculate the area a) 12 sq ins  Ans. b) 14 sq ins c) 16 sq ins A mound of soil is piled up into a cone of base diameter 1.8m and height 0.6 m. What is the volume of soil?  Ans. a) 0.5 m3 b) 1.5 m3 c) 1.0 m3 The heat of a resistor is given by the equation h = I2 RT. Find the current I. a)  Ans. b) c) What is the area of the shape below? a) 220 square inches b) 200 square inches  Ans. c) 196 square inches Factorise the following: x2 - x - 6 = 0: a) (x + 2) (x - 3) b) (x - 2) (x + 3)  Ans. c) (x + 2) (x - 3) 5/8 ths of 60 is a) 0.01  Ans. b) 37 1/2 c) 96 What is the supplement of 13 o 13' 13"?  Ans. a) 166o 66' 67" b) 276o 66' 67" c) 76o 66' 67" How many pairs of parallel sides has a trapezium? a) 0 pairs of parallel side...

2x2z2 (2x2 - 22)= a) 2x2z2 - 22 b) 4x2z2 - 44x2z2  Ans. c) 4x4z2 - 44x2z2 in 21 = 43 – X, X is equal to  Ans. a) 43 – 21 b) 43 + 21 c) 21 - 43 The comparison of the power input to the power output of an inverter is expressed as a  Ans. a) ratio b) loss c) gain The ratio of 6 : 4 can also be expressed as a) 64% b) 66%  Ans. c) 150% 200 kilo volts can be expressed as a) 2 x 103 volts b) 2 x 10-4 volts  Ans. c) 2 x 105 volts What is the surface area of a cone if the base is 8cm diameter and the length is 10cm?  Ans. a) 40p b) 80p c) 120p 2x2z2 (3x – z2) =  Ans. a) 6x3z2 - 2x2z4 b) 6x2z2 - 2x2z2 c) 6x2z2 + 3x – z2 What is the area of a rectangle when its height is 11cm and the width 120cm? a) 1320 m2  Ans. b) 0.132 m2 c) 1.32 m2 How many times does the X axis get crossed when y = x2 – 3 a) 1  Ans. b) 2 c) 3  What is an obtuse angle? a) an angle less than 90o  Ans. b) an angle between 90o and 180o c) an angle greater than 180o  4 3/...

In a right angle triangle, the cosine of an angle is a) opposite divided by hypotenuse  Ans. b) adjacent divided by hypotenuse c) opposite divided by adjacent Octal is to the base of a) 2 b) 16  Ans. c) 8 One radian is equal to  Ans. a) 57.5o b) 90o c) 75o The surface area of a cylinder of diameter 10 cm and height 10cm, is  Ans. a) 100p b) 50p c) 80p A parallelogram has a base 120cm and height 11 cm. What is the area? a) 1.32 m2  Ans. b) 0.132 m2 c) 0.0132 m2 The name given to this shape is  Ans. a) Parallelogram b)Trapezoid c) Rhombus The area of this shape is calculated by  Ans. a) Base x Height b) ½ Base x Height c) Perimeter squared The name of this shape is a) Parallelogram b) Trapezium  Ans. c) Rhombus The area of the shape is calculated by  Ans. a) ½ height x base b) ½ base x ½ height c) ½ height + twice base A triangle with equal sides is a) Isosceles b) Acute  Ans. c) Equilateral Two gears are in mesh, one has twice the number ...

What torque loading would you apply to a nut if the force is 50 lbs, exerted 2 feet from its axis?  Ans. a) 100 lbs.ft b) 251 lbs.ft c) 600 lbs.ft 67 divided by 127 is equal to a) 1/20  Ans. b) 1/128 c) ½ The formula for calculating the torque loading on a nut or bolt is a) Force used x diameter of the bolt  Ans. b) Force used x lever length of the spanner c) Lever length of the spanner Threads per inch Calculate the height of an obtuse triangle whose base is X cm and the area is Y square cm. a) Y x 2 x X B) Y + X 2  Ans. c) Y x 2 X How is the area of a circle calculated?  Ans. a) r2 x 3.142 b) d2 x 3.142 c) 2 x 3.142 x r Solve the following 9/4 + 5/12 + 1 3/8 =  Ans. a) 4 1/24 b) 2 25/24 c) 4 1/12 The specific torque loading for a bolt is 50 lbs.ins but an extension of 2” is needed to reach the bolt in addition to the 8” torque wrench. What will the actual reading? a) 54 lb.ins  Ans. b) 40 lb.ins c) 60 lb.ins Express the fraction 7 / 8 as a decimal ...