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## Related questions

A full adder is a combinational circuit that performs the arithmetic sum of three input bits and produces a (a) sum output (b) sum output and a carry (c) sum output with two carries (d) two sums with two carries

A half adder can be constructed from

The fast carry or look-ahead carry circuits found in most 4-bit parallel-adder circuits:  (1) Increase ripple delay (2) Add a 1 to complemented inputs (3) Reduce propagation delay (4) Determine sign and magnitude

Explain Center-tapped full wave rectifier with the help of circuit diagram and draw input output waveforms.

Explain full wave bridged rectifier with the help of circuit diagram and input output waveform.

A single phase 230 V/ 150 V , 1 kVA, 50 Hz transformer is supplied by 230 V AC supply. Find the full load primary and secondary current.

Shunt generator gives full voltage on load and the voltage drop as the load on the generator a. Decreases b. Increases c. Remains the same d. None of above

What will be the efficiency when the transformer operates at unity power factor and 60% of full load

An 8-pole alternator runs at 750 rpm and supplies power to a 6-pole induction motor which has a full load slip of 3 percent. The full load speed of the induction motor will be: A) 1000 rpm B) 920 rpm C) 950 rpm D) 970 rpm

Which of the following plants will take least time in starting from cold conditions to full-load operation? A) Nuclear power plant B) Steam power plant C) Hydro-electric power plant D) Gas turbine plant

Full load current of an Induction motor is 20 Ampere. The no-load current may be expected to be: A) 25 Ampere to 28 Ampere B) 15 Ampere to 18 Ampere C) 11 Ampere to 14 Ampere D) 6 Ampere to 10 Ampere

Full load copper loss in a transformer is 1600 watts. At half load the copper loss will be: A) 6400 watt B) 1600 watt C) 800 watt D) 400 watt

The full scale range of PMMC voltmeter is 100 V and its sensitivity is 1000 Ω/V. If the meter reads 50 V, the current through the voltmeter is (A) 0.05 mA (B) 0.5 mA (C) 5 mA (D) 50 mA

In a full wave rectifier with input frequency of 50 Hz, the frequency of the output is: (1) 50 Hz (2) 100 Hz (3) 150 Hz (4) 200 Hz

In a full wave rectifier circuit using centre tapped transformer, the peak voltage across half of the secondary winding is 30 V. Then PIV is: (1) 30 V (2) 60 V (3) 15 V (4) 10 V

A 0-10 A ammeter has a guaranteed accuracy of 1% of full scale deflection, the limiting error while reading 2.5 A will be (a) 1% (b) 2% (c) 4% (d) None of these

The constant of a given energy meter is 500 revolution/kWh. At the test 4.4 kW full load, meter completes 50 revolutions in 86 seconds. The percentage error of the meter is (a) –4.86% (b) 4.86% (c) 2.0% (d) 3.0%

Series resistance required to read 0-250 V with a moving coil instrument of internal resistance 2 ohm and full scale deflection of 50 mA is (a) 49998 Ω (b) 4998 Ω (c) 498 Ω (d) 49.8 Ω

A digital voltmeter has a read-out range from 0 to 9999 counts. When full scale reading is 9.999 V, the resolution of the instrument will be (a) 100 mV (b) 99 mV (c) 9 mV (d) 1 mV

The r.m.s. value of a half-wave rectified alternating current is 10 A. Its value for full-wave rectification will be

A separately excited d.c. motor fed from single phase full converter with firing angle 60° runs at 1000 r.p.m. If motor is connected to single phase semiconverter with the same firing angle of 60°, it would run at (a) 2000 rpm (b) 1850 rpm (c) 1500 rpm (d) 1000 rpm

A d.c. shunt motor runs at no load speed of 1140 r.p.m. At full load armature reaction weakens the main flux by 5%. Whereas the armature circuit voltage drops by 10%. The full load speed of the motor is (a) 1200 r.p.m. (b) 1080 r.p.m. (c) 1040 r.p.m. (d) 1000 r.p.m.

A permanent magnet moving coil ammeter has a coil resistance of 99 ohm and Full Scale Deflection (FSD) current of 0.1mA. Shunt resistance is 1 ohm. Current through the meter at 0.5 F.S.D is:

A single phase full-wave half-controlled bridge converter feeds an inductive load. The two SCRs in the converter are connected to a common DC bus. The converter has to have a freewheeling diode.  (A) because the converter inherently does not provide for free-wheeling (B) because the converter does not provide for free-wheeling for high ... the AC supply (D) or else if a gate pulse to one of the SCRs is missed, it will subsequently cause a high load current in the other SCR.

A simple phase transformer has a maximum efficiency of 90% at full load and unity power factor. Efficiency at half load at the same power factor is  (A) 86.7% (B) 88.26% (C) 88.9% (D) 87.8%

A 400 V, 15 kW, 4-pole, 50 Hz, Y-connected induction motor has full load slip of 4%. The output torque of the machine at full load is  (A) 1.66 Nm (B) 95.50 Nm (C) 99.47 Nm (D) 624.73 Nm

The type of single-phase induction motor having the highest power factor at full load is (A) shaded pole type (B) split-phase type (C) capacitor-start type (D) capacitor-run type

A 500 kVA, 3-phase transformer has iron losses of 300 W and full load copper losses of 600 W. The percentage load at which the transformer is expected to have maximum efficiency is  (A) 50.0% (B) 70.7% (C) 141.4% (D) 200.0%

A single-phase, 50 kVA, 250 V/500 V two winding transformer has an efficiency of 95% at full load, unity power factor. If it is re-configured as a 500 V/750 V auto-transformer, its efficiency at its new rated load at unity power factor will be  (A) 95.752% (B) 97.851% (C) 98.276% (D) 99.241%

The dc motor, which can provide zero speed regulation at full load without any controller is  (A) series (B) shunt (C) cumulative compound (D) differential compound

An induction motor having full load torque of 60 Nm when delta connected develops a starting torque of 120 Nm. For the same supply voltage if the motor is changed to star connection, the starting torque developed will be  A) 40 Nm B) 60 Nm C) 90 Nm D) 120 Nm

a single phase full wave midpoint thyristor converter uses a 230/200V transformer with centre tap on the secondary side. The P.I.V per thyristor is   (A) 100V (B)141.4V (C)200V (D)282.8V

In a full wave rectifier the negative point in a circuit is   (A) cathode (B) anode (C) The central tap on the high voltage secondary (D) plate.

The transformer utilization factor of full wave bridge rectifier is   (A) 0.812 (B) 0.286 (C) 0.693 (D) 0.782

A moving coil instrument has a resistance of 10 W and gives full scale deflection when carrying a current of 50 mA. To measure current upto 100 A, we will have to connect • 10 W resistance in series • 10 W resistance in parallel • 10/1999 W resistance in series • 10/1999 W resistance in parallel

In a transformer, zero voltage regulation at full load is   (a)Not possible   (b) Possible at unity power factor load   (c) Possible at leading power factor load   (d) Possible at lagging power factor load

In a single-phase full converter, the number of SCRs conducting during overlap is   (a) 1 (b) 2 (c) 3 (d) 4

A single-phase full-bridge diode rectifier delivers a load current of 10A, which is ripple free. Average and rms values of diode currents are respectively   (a) 10A, 7.07A (b) 5A, 10A (c) 5A, 7.07A (d) 7.07A, 5A

A consumer finds that after running 10 kVA equipment on full load for six hours, his energy consumption was 48 kWH. It can be concluded that (A) The load factor of consumer for the day was unity. (B) The maximum demand of consumer is 10 kW. (C) The equipment was drawing only reactive power. (D) The power factor of equipment was 0.8.

What is the full form of "HDMI" port?

A 40 kVA transformer has a core loss of 400 W and a full load copper loss of 800 W. The proportion of full load at maximum efficiency is

A four -quadrant operation requires two full converters connected in  (1) Series (3) Back to back (2) Parallel (4) Series Cascade

An ac voltmeter using full -wave rectification and having a sinusoidal input has an ac sensitivity equal to  (1) 1.414 times dc sensitivity (2) dc sensitivity (3) 0.9 times dc sensitivity (4) 0.707 times dc sensitivity

A transformer operates 24 hours day at full -load. It's full -load efficiency is :  (A) equal all day efficiency (B) more than all -day efficiency (C) less than all -day efficiency (D) equal to maximum efficiency

At full -load of a transformer, the iron loss and copper loss are 3000 W and 4000 W respectively. Then total loss at maximum efficiency is :  (A) 7000 W (B) 6000 W (C) 8000 W (D) 4000 W

The ratio of full -load volt-amperes to short-circuit volt-amperes is equal to :