Technical Test SSC JE: Electrical Engineering (EE)- 9

In the following type of conductors the corona is minimum in

Consider the following w.r.t. the circuit as shown below

Which of the above statements is/are correct?

If the time delay of relay with TMS setting 0.1 is 10 second then what is the time delay when the TMS setting is changed to 0.5

The machine used in wind will is

In an RLC series resonant circuit, if the maximum stored energy is increased by 10%and at the same time, the energy dissipated per cycle is reduced by 10%, it will result in which one of the following ?

Consider the following components Out of these components, which component(s)can be common for primary & back up protection

In a series resonance circuit, at resonance selectivity Q is equal to

Positive sequence terminal voltage is zero in

Most economical load in the underground cable is

In distribution lines

A certain network consist of a large number of ideal linear resistances, one of which is
designated consumed by R is P1 when only the first source is active, and P2 when only the
second source is active, if both source are active simultaneously, then the power consumed by R
is
 

Consider the following statement about D'Arsonval Movement
1. It is best suited for d.c. current measurement
2. It responds to the average value of current
3. It could be used for power measurements

Which of these statements is/are correct
 

Torque/weight ratio of an instrument indicates

A current transformer has a phase error of +3º. The phase angle between the primary andsecondary current is

The direction of rotation of a d.c. series motor can be changed by

A three phase transformer having zero sequence impedance of Zo has the zero-sequence network as shown in the figure below. The connection of its windings are

The transformer laminations are insulated from each other by

A coil with certain number of turns has a specified time constant. If the no. of turns is doubled, its time constant would

The technique of adding a precise amount of time between the trigger point and the beginning of the scope-sweep in a CRO is known as

In a CE (common emitter) transistor, V_CC = 12V and the zero signal collector current is 1mA. Determine the operating point when collector load (R_C) is 6 KW

A 100 H.P. motor with a synchronous speed of 720 rpm at 50 Hz has 96 stator slots with4 conductors per slot and 120 rotor slots with 2 conductors per slot. If the full load efficiency is 0.92 and the p.f. is 0.9 lagging, the current per phase when the stator is star connected to3-phase, 500V supply will be

Which of the following application requires high starting torque ?

Which DC motor will be preferred for machine tools ?

The empty space between the plates of a capacitor is filled with liquid of dielectricconstant K the capacitance of capacitor

If current through the operating coil of a moving iron instrument is doubled, the operating forcebecomes

A magnetic needle is kept in a uniform magnetic field. It experiences

Disadvantage of low p.f. is

For improvement of power factor

A 4-pole 500V shunt motor has 720 wave connected conductors on its armature. The fullload armature current is 60A and flux per pole is 0.03 Wb. The armature resistance is 0.2 Wand the contact drop per brush is 1V. What is the back emf ?

In an autotransformer of voltage ratio the fraction of power transferred
inductively is proportional to

Stepped core is used in transformers in order to reduce

A make break switch is provided to disconnect the battery when the meter is not in use is

Which instrument is the cheapest, disregarding the accuracy

In dc machines, the armature reaction mmf is

Inductance affects the flow of direct current at the time of

A centre zero ohmmeter connected in the rotor circuit of 6-pole 50 Hz induction motor makes30 oscillations in one minutes. The rotor speed is

A coil of resistance 20W and inductance 0.8 H is connected to a 200V DC supply. The rate
of change of current at t = 0+ is

What should be the value of resistance R, in the above circuit if it has to absorb the maximum
power from the source

The torque on the rotor of a  motor is more constant than that of a single phase motor because

When the secondary coil of a transformer is short circuited, the primary inductance

Q-factor of a parallel tuned circuit can bei ncreased by

Air blast circuit breakers for 400 KV power system are designed to operate in

An overhead line conductor has an inductance per unit length of L Henry. If the entire medium
around the conductor is filled with a dielectric material of permittivity (E), then the inductance
will be
 

In two-wattmeter method of power measurement one of the watt meter will show negative reading when the load pf angle is strictly

A reactance relay is

To limit current chopping in vacuum circuit breakers, the contact

The main difference between speed-time curves of main line service as compared to sub urban services in

Which of the following relay has directional feature

Carbon brushes are preferable to copper brushes because

A power plant has a maximum demand of 15 MW. The load factor is 50% and the plant factor is 40%. The operating reserve is

The starting torque of a servomotor under unbalanced operation is proportional to

Quadrilateral speed-time curve is the closer approximation for

Travelling crane is used for lifting and moving heavy loads. It uses

For Domestic wiring method commonly used is

The time taken for a surge to travel a 600 km long overhead transmission link is

Ripple factor of half wave rectifier is

Which one is unipolar transistor

A polarized electrolytic capacitor can be used

162.A moving coil instrument gives full scale deflection with a current of 100 mA when the potential difference across its terminals is 50mV. Calculate the shunt resistance to enable the instrument to read upto 100 A

Which of the following motors are used in tape recorders

Which motor would you select for vacuum cleaner

A tank circuit consist of

The commutator in a dc machine acts as

Formative time lag depends on the mechanism of the avalanche growth in gap. The formative time lag is usually

EHV cables are filled with thin oil under pressure

Arcing on transmission lines is prevented by connecting a suitable

In half wave rectifier, if an a.c. supply is 60 Hz, then what is the a.c. ripple at output ?

A power supply has full load voltage of 24V. What is the no load voltage for 5% regulation?

For an existing ac transmission line, the string efficiency is 80%. If dc voltage is supplied for the same set up, the string efficiency will be

When excitation is altered in an alternator connected to an infinite line, it provides a corresponding change in

Lightening surges are arrested by

The rms value of a half wave rectified current is 10A. Its value for full wave rectification would be

For the wave given below, the rms value will be

The equation for 25 cycles current sine wave having rms value of 30 amperes will be

A 220 V series motor takes a current 35 amp and runs at 500 rpm. Armature resistance = and series field resistance = . If iron and friction losses amount to Whatis the armature torque

Illumination level required for precision work is around

Lumen/watt is the unit of

A DC generator used for ac welding should have

The load taken by welding transformer is

In rectifier circuit shown above, what should be minimum peak-inverse voltage (PIV) rating of the diode

In an open circuited p-n junction diode space charge density at the junction is

In an HVDC system

In order to have lower cost of power generation

Mho relay is usually employed for the protection of

The making and breaking currents of 3- f ac circuit breakers in power system are respectively in what form

For a fault in power system, the term critical clearing time is related to

A cable has inductance of 0.22 mH per km and capacitance of 0.22 per km. The surge
impedance of the cable is

The shunt winding of a motor has a resistance of 85W at 22ºC. When the motor runs at full load, its resistance increases to 100 ohms. There sistance temperature coefficient of winding per OºC is 0.004. The rise in temperature of the winding will be nearly

Temperature coefficient of resistance is expressed in terms of

For the same peak value of voltage which wave will have the highest rms value ?

 A wire 2.5m long is bent into a square. A current of 100 A flowing through the wire will producea magnetising force at the centre of the square,equal to

Common base configuration is little used because

The decrease in terminal voltage of a shuntn generator is due to

The armature voltage control is considered as suitable, in case the dc machine is driven at

Interpoles are usually wound with

If the flux of dc motor approaches zero

Which of the following is not a routine test on transformers