1. Find the current in the circuit.

a) 10 A b) 20 A c) 30 A d) 40 A

Answer: Option (b) Explanation: I=V/R. Total resistance = 20+40=60ohm. I=120V. I=120/60=20A.
2. The resistivity of the conductor depends on

a) area of the conductor. b) length of the conductor. c) type of material. d) none of these.

Answer: Option (c) Explanation: The resistivity is a property of material, defined as the resistance between two opposite faces of a cube of a material of unit volume. That is why resistivity is only the unique property of material and it does not depend upon the dimension of any piece of material.
3. The resistance of a conductor of diameter d and length l is R Ω. If the diameter of the conductor is halved and its length is doubled, the resistance will be

a) R Ω b) 2R Ω c) 4R Ω d) 8R Ω

Answer: Option (d) Explanation: As per law of resistance, the resistance of the conductor is inversely proportional to its cross-sectional area i.e. it is inversely proportional to the square of the diameter of cross-sectional area of the conductor. As per same law of resistance, the resistance of the conductor is directly proportional to the length of the conductor.
4. How many coulombs of charge flow through a circuit carrying a current of 10 A in 1 minute?

a) 10 b) 60 c) 600 d) 1200

Answer: Option (c) Explanation: 1 Ampere current means flowing of 1 Coulomb charge per second. That means 10 A current in 1 minute or 60 seconds implies 10 × 60 = 600 coulombs.
5. A capacitor carries a charge of 0.1 C at 5 V. Its capacitance is

a) 0.02 F b) 0.5 F c) 0.05 F d) 0.2 F

Answer: Option (a) Explanation: The capacitance of a capacitor is expressed by Q/V. Where Q is the charge of the capacitor and V is the voltage across the capacitor.
6. To obtain a high value of capacitance, the permittivity of dielectric medium should be

a) low b) zero c) high d) unity

Answer: Option (c)
7. Four capacitors each of 40 µF are connected in parallel, the equivalent capacitance of the system will be

a) 160 µF b) 10 µF c) 40 µF d) 5 µF

Answer: Option (a) Explanation: The impedance of a capacitor is inversely proportional to its capacitance value. Reciprocal of equivalent impedance of parallel connected circuit elements is sum of reciprocal of impedance of each of the elements.
8. Instantaneous power in inductor is proportional to the

a) product of the instantaneous current and rate of change of current. b) square of instantaneous current. c) square of the rate of change of current. d) temperature of the inductor.

Answer: Option (a) Explanation: The instantaneous voltage across the inductor is expressed as the product of inductance and rate of change of current through it. Power is expressed as the product of current and voltage. Hence instantaneous power in an inductor is proportional to the product of instantaneous current and rate of change of current through it.
9. If all the elements in a particular network are linear, then the superposition theorem would hold, when the excitation is

a) DC only b) AC only c) Either AC or DC d) An Impulse

Answer: Option (c) Explanation: Superposition theorem can be applied for both AC as well DC excitation to calculate the voltage or current calculations. It holds for both DC and AC excitation, if the circuit is linear. But superposition theorem is not applicable for power calculations.
10. In balanced bridge, if the positions of detector and source are interchanged, the bridge will still remain balanced. This can be explained from which theoem

a) Reciprocity theorem b) Thevinin's theorem c) Norton's theorem d) Compensation theorem

Answer: Option (a) Explanation: When response to excitation is constant even though we interchange the excitation and responses then the reciprocity theorem is verified for the given network.

1. To implement the linear time invariant recursive system described by the difference equation y(n)=[latex]\displaystyle\sum_{k=1}^{N} a_k y(n-k)+\displaystyle\sum_{k=0}^{M}b_kx(n-k)[/latex] in Direct form-I, how many number of delay elements and multipliers are required respectively?

a) M+N+1,M+N b) M+N-1,M+N c) M+N,M+N+1 d) None of the mentioned

Answer: Option (c) Explanation: Explanation: From the given equation, there are M+N delays, so it requires M+N number of delay elements and it has to perform M+N+1 multiplications, so it require that many number of multipliers.
2. The system represented by the following direct form structure is:

a) General second order system b) Purely recursive system c) Partial recursive system d) FIR system

Answer: Option (d) Explanation: The output of the system according to the direct form given is y(n)= b0x(n)+b1x(n-1)+b2x(n-2) Since the output of the system is purely dependent on the present and past values of the input, the system is called as FIR system.
3. Which of the following should be done in order to convert a continuous-time signal to a discrete-time signal?

a) Sampling b) Differentiating c) Integrating d) None of the mentioned

Answer: Option (a) Explanation: The process of converting a continuous-time signal into a discrete-time signal by taking samples of continuous time signal at discrete time instants is known as ‘sampling’.
4. The process of converting discrete-time continuous valued signal into discrete-time discrete valued(digital) signal is known as:

a) Sampling b) Quantization c) Coding d) None of the mentioned

Answer: Option (b) Explanation: In this process, the value of each signal sample is represented by a value selected from a finite set of possible values. Hence this process is known as ‘quantization’
5. The difference between the unquantized x(n) and quantized xq(n) is known as:

a) Quantization coefficient b) Quantization ratio c) Quantization factor d) Quantization error

Answer: Option (d) Explanation: Quantization error is the difference in the signal obtained after sampling i.e., x(n) and the signal obtained after quantization i.e., xq(n) at any instant of time.
6. Which bit coder is required to code a signal with 16 levels?

a) 8 bit b) 4 bit c) 2 bit d) 1 bit

Answer: Option (b) Explanation: To code a signal with L number of levels, we require a coder with (log L/log 2) number of bits. So, log16/log2=4 bit coder is required.
7. What is the spectrum that is obtained when we plot |ck| as a function of frequency?

a) Magnitude voltage spectrum b) Phase spectrum c) Power spectrum d) None of the mentioned

Answer: Option (a) Explanation: We know that, Fourier series coefficients are complex valued, so we can represent ck in the following way. ck=|ck|[latex]e^\text{jθk}[/latex] When we plot |ck| as a function of frequency, the spectrum thus obtained is known as Magnitude voltage spectrum.
8. Which of the following is used in the realization of a system?

a) Delay elements b) Multipliers c) Adders d) All of the mentioned

Answer: Option (d) Explanation: From each set of equations, we can construct a block diagram consisting of an interconnection of delay elements, multipliers and adders.
9. Computational complexity refers to the number of:

a) Additions b) Arithmetic operations c) Multiplications d) None of the mentioned

Answer: Option (d) Explanation: Computational complexity is one of the factor which is used in the implementation of the system. It refers to the numbers of Arithmetic operations (Additions, multiplications and divisions).
10. Which of the following refers the number of memory locations required to store the system parameters, past inputs, past outputs and any intermediate computed values?

a) Computational complexity b) Finite world length effect c) Memory requirements d) None of the mentioned

Answer: Option (c) Explanation: Memory requirements refers the number of memory locations required to store the system parameters, past inputs, past outputs and any intermediate computed values.

1. The peak value of a sine wave is 200 V. Its average value is

a) 127.4 V b) 141.4 V c) 282.8 V d) 200V

Answer: Option (a)
2. Two waves of the same frequency have opposite phase when the phase angle between them is

a) 360° b) 180° c) 90° d) 0°

Answer: Option (b)
3. The best place to install a capacitor is

a) very near to inductive load b) across the terminals of the inductive load c) far away from the inductive load d) any where

Answer: Option (b)
4. Inductance affects the direct current flow

a) only at the time of turning off b) only at the time of turning on c) at the time of turning on and off d) at all the time of operation

Answer: Option (c)
5. The double energy transient occur in the

a) purely inductive circuit b) R-L circuit c) R-C circuit d) R-L-C circuit

Answer: Option (d)
6. The absolute thermodynamic temperature scale is also known as

a) celsius scale b) kelvin scale c) fahrenheit scale d) none of the mentioned

Answer: Option (b) Explanation: It was proposed by Kelvin.
7. In defining the temperature scale, the standard reference point is taken as

a) zero kelvin b) boiling point of water c) triple point of water d) none of the mentioned

Answer: Option (c) Explanation: Triple point of water is taken as the standard reference point.
8. If the temperature of intake air in internal combustion engine increases, then its efficiency will

a) Remain same b) Decrease c) Increase d) None of these

Answer: Option (b)
9. The operation of forcing additional air under pressure in the engine cylinder is known as

a) Scavenging b) Turbulence c) Supercharging d) Pre-ignition

Answer: Option (c)
10. The mean effective pressure obtained from engine indicator indicates the

a) Maximum pressure developed b) Minimum pressure c) Instantaneous pressure at any instant d) Average pressure

Answer: Option (d)

1. The function of crankcase in two stroke petrol engines is

a) It holds the engine lubricating oil b) It forms a pressurised chamber for fuel air mixture c) It holds the exhaust gases after combustion d) None of the mentioned

Answer: Option (b) Explanation: It holds the fuel air mixture during engine cycle.
2. Connecting rods are generally of the following form

a) Forged I-section b) Forged round section c) Cast iron square section d) Forged square section steel

Answer: Option (a) Explanation: Connecting rods are generally of forged I-section type.
3. The purpose of crankcase ventilation is to

a) Cool the oil b) Remove vaporised water and fuel c) Supply oxygen to the crankcase d) It assists in maintaining the viscosity of oil

Answer: Option (b) Explanation: Crankcase ventilation removes vaporised water and fuel.
4. The escape of burned gases from the combustion chamber past the pistons and into the crankcase is called

a) Gas loss b) Blow by c) By pass d) Passed gas

Answer: Option (b) Explanation: Blow by is the surging of burned gases from combustion chamber into the crankcase.
5. Piston compression rings are made of

a) Cast iron b) Steel c) Aluminium d) Bronze

Answer: Option (a) Explanation: Cast iron is used for piston compression rings.
6. The purpose of a piston pin is that

a) It prevents the valve from rotating b) It links the connecting rod to the crankshaft c) It ensure the piston ring to the piston d) It connect the piston to the connecting rod

Answer: Option (d) Explanation: Piston pin connects the piston to the connecting rod.
7. Passenger car engines contain

a) 2 compression ring and 1 oil control ring b) 2 compression ring and 2 oil control ring c) 1 compression ring and 1 oil control ring d) 2 compression ring and no oil control ring

Answer: Option (a) Explanation: These type of engines contain 2 compression ring and 1 oil control ring.
8. The plate which acts as a packing between cylinder block and cylinder head is called

a) Chaplet b) Liner c) Gasket d) Flange

Answer: Option (c) Explanation: Gasket forms the packing between cylinder block and cylinder head
9. Which one of the following is a type of Gasket

a) Copper asbestos b) Steel asbestos c) Single sheet rigid d) All of the mentioned

Answer: Option (d) Explanation: All the three are various types of gaskets.
10. The opening and closing of a valve is respectively done by

a) A cam and a spring b) A spring and a cam c) Gas pressure and cam d) Cylinder vacuum and spring

Answer: Option (a) Explanation: An engine valve is opened by a cam and closed by a spring.

1. What is the maximum limit of sound intensity in decibel units beyond which a human being cannot hear?

a) 80 decibel b) 85 decibel c) 90 decibel d) 95 decibel

Answer: Option (b)
2. Who proposed the ‘Wave Theory’ of light?

a) Huygens b) Albert Einstein c) Isaac Newton d) Thomas Edison

Answer: Option (a)
3. If a bar magnet is broken into two pieces, then

a) one piece will have North Pole on both ends and other piece will have South Pole on both ends b) only longer piece will behave as bar magnet c) each piece will remain a magnet with North Pole at one end and South Pole at the other end d) both pieces will lose their magnetism

Answer: Option (c)
4. Why does a corked bottle filled with water break when frozen

a) glass is a bad conductor of heat b) the bottle contracts on freezing c) volume of water decreases on freezing d) volume of water increases on freezing

Answer: Option (d)
5. Wood is the primary raw material for the manufacture of:

a) paint b) paper c) ink d) gun powder

Answer: Option (b)
6. Spondylitis is a disease that affects:

a) liver b) intestine c) spinal column d) brain cells

Answer: Option (c)
7. What is the chemical name of laughing gas?

a) Carbon monoxide b) Sulphur dioxide c) Hydrogen peroxide d) Nitrous Oxide

Answer: Option (d)
8. The filament of an electric bulb is made up of which material?

a) tungsten b) iron c) stainless steel d) graphite

Answer: Option (a)
9. Diamond is an allotropic form of:

a) Uranium b) Carbon c) Silicon d) Sulphur

Answer: Option (b)
10. The mass on any substance liberated from an electrolyte is directly proportional to the quantity of charge passing through the solution.

a) Avogadro’s law b) Faraday’s first law of electrolysis c) Stefan’s law d) Kirchhoff’s law of electricity

Answer: Option (b)

1. The ratio of two numbers is 4:7 and their HCF is 6. Find out their LCM

a) 164 b) 168 c) 174 d) 184

Answer: Option (b) Explanation: The two numbers will be 4*6 =24 and 7*6=42. The LCM of 24 and 42 will be 168
2. The ratio of two numbers is 3:4 and their sum is 560. What is the larger number

a) 240 b) 320 c) 340 d) 416

Answer: Option (b) Explanation: Here 3x+4x=560 or x=80 and the larger number is 320
3. Vacancies for Engineers, Diploma and Artisan were in the ratio of 5:7:8 and it was decided to increase by 40, 50 and 75%. What will be the revised ratio

a) (3:4:5) b) 4:5:6) c) (2:3:4) d) (5:6:7)

Answer: Option (c) Explanation: Let x be the HCF of the existing ratio that the vacancies were 5x, 7x and 8x. Now with the increase, it will become (5x+2x), (7x+3.5x) and 8x+6x) and HCF of these numbers will now become 2:3:4
4. An old man gave away 1/5th of his property to Ram, 1/3rd of the remaining to Shyam and 1/2 of the remaining to Geeta. How much part he is left?

a) (4/15) b) (2/15) c) (8/15) d) (1/5)

Answer: Option (a) Explanation: Let he has x amount of which he gives x/5 to Ram, left 4x/5 and gave 1/3 of this shyam i.e. 4x/15 and left with 8x/15 of which he gave 4x/15 to Geeta and thus left with 4x/15.
5. The condition that does not satisfy the condition of their being congruent is

a) all three sides equal b) all three angles equal c) two sides and the angle enclosed are equal d) the two angles and the side enclosed by them are equal

Answer: Option (b) Explanation: If all the three angles are same, it need not be congruent as the sides can be unequal.
6. What is the relation to find the diagonals of a polygons with number of side as ‘n’

a) (n²-1)/2 for odd sides and n²/2 for even sides b) (n-1)(n-3)/2 c) (n-2)(n-3)/2 d) n(n-3)/2

Answer: Option (d) Explanation: The relation is given as n(n-3)/2
7. Pythagorean triplets are

a) 2m, m²-1, m²+1 b) \m, m²-1, m²+1 c) 2m, 2m²-1, 2m²+1 d) 2m, m², m²+1

Answer: Option (a) Explanation: Pythagoras triplets are given for any natural number m which is greater than one
8. 6 pipes can fill the tank in 1 hour and 20 minutes. How much time in minutes it will take it to fill by 5 pipes.

a) 80 b) 200/3 c) 96 d) 106

Answer: Option (c) Explanation: 6 pipes take 80 minutes than one pipe will take 6*80=480 and five pipe 480/5=96 minutes
9. A can do a piece of work in 15 days and B alone can do it in 10 days. B works at it for 5 days and then leaves. A alone can finish the remaining work in

a) 2 b) 2.5 c) 3.5 d) 3

Answer: Option (b) Explanation: Capacity of A is 1/15 and B is 1/10. Work completed in 5 days is 1/3+1/2=5/6 and 1/6 is remaining which will be completed by A in 15/6 days i.e. 2.5 days
10. By what percentage the interest amount received after six year is more as compared to the amount after five years on Rs. 1000/- compounded at an interest of 10% is given by

a) 0.1 b) 0.1001 c) 0.1002 d) 0.1003

Answer: Option (a) Explanation: Every year the interest is on the accumulated amount consisting of principle and interest and thus it will gain by the interest rate given.