1/100
Two copper conductors have equal length. The cross sectional area of one conductor is four times that of the other. If the conductor having smaller cross sectional area has a resistance of 40 ohms, the resistance of other conductor will be
2/100
What will be the direction of the drift velocity of electrons change in semiconductors with respect to the electric field?
3/100
Voltage across 60 ohm resistor is
4/100
An EMF produced in a moving conductor coil is in accordance with the following law
5/100
Which of the following statements is TRUE for series and parallel operation of DC circuit?
6/100
Inside of a conducting sphere, which of the following is constant?
7/100
In semiconductors, the conduction of electricity is due to the movement of which of the following?
8/100
If the number of turns and length of a solenoid are doubled, its axial magnetizing field will be --------
9/100
A Commutator in DC generator can 1.Provide half-wave rectification 2.Provides full-wave rectification 3.converts dc to ac, 4.converts ac to dc 5.provide controlled full-wave rectification.
10/100
If suppose OCC is conducted at speed N1 speed, where N1< Nrated. OCC will lie
11/100
In de machines, the field flux and armature-numf axis are respectively along the
12/100
Ina D.C. machine, iron losses are independent of variations in
13/100
If a DC shunt motor is working at full load and if shunt field circuit suddenly opens
14/100
In D.C. generators on no-load, the air gap flux distribution in space is
15/100
No load speed of the DC shunt motor is 1322 rpm while full load speed is 1182 rpm. What will be the speed regulation?
16/100
Which of the following is not the method of electrical braking?
17/100
A moving-coil permanent-magnet instrument can be used as ------- by using A low resistance shunt.
18/100
Induction type instruments are used for
19/100
If at one end, the two wires made of different metals are joined together then a voltage will get produced between the two wires due to difference of temp between the two ends of wires. This effect is observed in
20/100
The errors in current transformers can be reduced by designing them with
21/100
What is the magnimde of the voltage developed across the capacitor in a series RLC circuit at resonance?
22/100
capacitor has capacitance C and reactance X. if capacitance and frequency become double, then reactance will be
23/100
In a L-C series circuit, if XL>Xc. Then the current is
24/100
In a two wattmeter method of measuring the power in a 3-phase balanced system. what is the power factor of the load when one wattmeter reads twice the other.
25/100
Current of 50 /π Hz frequency is passing through an AC circuit having series combination of resistance R= 100 Ω and L= 1 H. then phase difference between voltage and current is
26/100
What is the magnitude of mutually induced emf. E₂ in a transformer?
27/100
Which of the following current is drawn by the primary circuit of an ideal transformer when the secondary is open?
28/100
The no-load power factor of a practical transformer is around
29/100
If number of turns in primary and secondary coils of a transformer increased to two times each, the mutual inductance
30/100
In a transformer, zero voltage regulation at full load is
31/100
A 400/200V transformer has total resistance of 0.02 pa on its LV side. This resistance when referred to HV side would be
32/100
What is the functionality of a breather in a transformer?
33/100
In a synchronous alternator, which of the following coils will have emf closer to sine wave form?
34/100
When an altemator designed for operation at 60 Hz is operated at 50 Hz
35/100
Two alternators are in parallel for taking one of the alternators out of the system
36/100
A synchronous motor has no starting torque because of
37/100
A synchronous motor can be used as a synchronous capacitor when it is
38/100
A 10 pole, 25 Hz alternator is directly coupled to and is driven by 60 Hz synchronous motor. What is the number of poles for the synchronous motor?
39/100
A 3-phase squirrel cage induction motor designed to operate with stator in star, needs W kg of copper for its stator winding. Now if this motor is to be designed to operate with stator in delta, then weight of copper required for stator would be
40/100
The effect of leakage flux in case of 3-phase induction motor is
41/100
Air gap of a poly-phase induction motor is kept small to
42/100
The value of operating power factor of a 3-phase induction motor is high when
43/100
Pick the correct statements regarding 1-phase induction motors?
44/100
The type of single-phase induction motor having the highest power factor at full-load is
45/100
The most economical power factor for a consumer is
46/100
Which of the following is the essential requirement of peak load plant?
47/100
The area under the load curve gives
48/100
The efficiency of a thermal power plant improves with
49/100
Which of the following place is not associated with the nuclear power plants in India
50/100
Skin effect is proportional to
51/100
In overhead transmission lines the effect of capacitance can be neglected when the length of line is less than
52/100
Corona usually occurs when the electrostatic stress in the air around the conductor succeeds .
53/100
The characteristic impedance of a transmission line depends upon
54/100
The resistance of an electric arc can be increased by
55/100
Pin insulators are normally used up to voltage of about
56/100
Circuit breakers usually operate under
57/100
A differential relay measures the vector difference between
58/100
The inductance of a single phase two wire line is given by (D is the distance between conductors and "2r" is the diameter of conductor)
59/100
The maximum demand of a consumer is 2kW and his daily energy consumption is 20 units. His load factor is
60/100
The most economical load on an overhead line is
61/100
In case the height of transmission tower is increased
62/100
A 70/6 ACSR conductor is an aluminium conductor steel reinforced having
63/100
Out of the following systems of distribution, which system offers the best economy?
64/100
In terms of constants A, B, C and D for short transmission lines, which of the following relation is valid?
65/100
Long distance railways use ------- supply
66/100
Which of the following services uses the quadrilateral type of speed-time operations?
67/100
The air resistance to the movement of the train is proportional to
68/100
The coefficient of adhesion is highest when
69/100
Single-phase to three-phase system in electric traction is also called as
70/100
A train has a schedule speed of 36 km per hour on a level track. If the distance between the stations is 2 km and the stoppage is 30 seconds the actual time of run will be
71/100
The speed curve for a local trian is shown in Figure in this AB represent
72/100
In electric traction system. quadrilateral speed-time curve is the closer approximation for
73/100
Under the influence of fluorescent lamps sometimes the wheels of rotating machinery appear to be stationary. This is due to the
74/100
The size of the earth or ground wire is based on
75/100
What should be the value of earthing resistance for large power stations?
76/100
What is the formula used to calculate the number of poles required in LT line distribution?
77/100
The current passing through the resistance R1 in the following circuit is when the diodes are ideal devices
78/100
What is the potential difference between A and B terminals of the given circuit
79/100
Long distance railways use ------- supply
80/100
In order to prevent distortion in the output signal after amplification, the input signal must be
81/100
One of the condition for oscillation is
82/100
In order to start up, a feedback oscillator requires
83/100
One condition for positive feedback is that the phase shift around the feedback loop must be
84/100
To get the outpur 1 for the following circuit, the correct choice of the inputs are:
85/100
The following figure shows a logic gate circuit with the two inputs A and B and the output Y. The voltage waveforms of AB and Y are as given below, the logic gate is
86/100
The following circuit is equivalent to
87/100
The correct Boolean operation represented by the circuit diagram drawn is
88/100
How many bytes of bit addressable memory is present in 8051 based microcontrollers?
89/100
Which out of the four ports of 8051 needs a pull-up resistor for using it is as an input or an output port?
90/100
Which addressing mode is used in pushing or popping any element on or from the stack?
91/100
Function of EA pin in 8051 is
92/100
If the tum on time of an SCR is 15microseconds, then what is the width of the gate pulse which is required to trigger the SCR reliably?
93/100
What is the latching current of a SCR?
94/100
Which of the following device is latching device?
95/100
Which of the following device does not have gate terminal?
96/100
In single phase fully controlled rectifier, if the firing angle is 90 degrees for RL load under continuous conduction, then the average voltage of the load is ---------
97/100
A three phase fully controlled converter, if delay angle is 30 degrees and power factor angle between its input voltage and current is 45 degrees, then the converter operates --------- mode
98/100
In dc choppers, if the input voltage is 100V and output voltage is 50 V. for the switching frequency of 1.0 kHz, what is the ON period of the Thyristor switch?
99/100
Which of the following device is the most suitable for high-frequency conversion in SMPS?
100/100
For single-phase step-up cyclo-converter ----------- type of commutation is required for thyristor switches
Result: