When the r.m.s. output voltage of a full-wave bridge rectifier is 20 V, the PIV across the diodes (neglecting diode drop) is
Question 2
The B-H curve for……. will be a straight line passing through the origin.
Question 3
A permanent magnet moving coil ammeter is connected in 50 Hz a.c. circuit in which 5 A current is flowing. If the meter remains connected in the circuit for some time,
Question 4
In the armature winding of an alternator, the coil span falls short of full-pitch by (electrical). The pitch factor is ………………
Question 5
In a circuit breaker, What is the condition of arc will not restrike:
Question 6
After closing the switch S at t=0, the current i(t) at any instant t in the below network is
Question 7
If a unit step current is passed through a capacitor what will be the voltage across the capacitor?
Question 8
If the magnetising force required at the working flux density in Fig. is 400 AT/m (from B-H curve), the required number of turns is
Question 9
Fig. A. shows the transistor circuit and Fig. B. its d.c. load line. What will be the value of
Question 10
A two-pole alternator is running at 1500 r.p.m. Its angular velocity is …………………..
Question 11
Two resistors of resistances are connected in parallel. The power dissipated in resistor is 9 W. The power dissipated is resistor is
Question 12
Fig. shows the output characteristics of a transistor and d.c. load line. What will be the operating point when base current is
Question 13
In a transformer, which among the following statement is correct with respect to short-circuit test?
Question 14
A capacitor of 100 μF stores 10 mJ of energy. What is the amount of charge (in Coulomb) stored in it?
Question 15
A voltage regulation test is to be performed on a 3-phase Y-connected alternator. Its line-to-line voltage drop is taken with a d.c. supply to find its armature circuit resistance. The readings are : d.c. voltage drop = 11.15 V and line current = 18.5 What is the per phase d.c. resistance?
Question 16
The range of a permanent-magnet moving coil instrument is 0-10 A. If the full-scale deflection current of the meter is 2 mA, then multiplying power of the shunt is …………….
Question 17
How would the loop in Fig. appear for a material with much less retentivity?
Question 18
Fig. shows the transistor in common base arrangement. The leakage current in the collector region is…………………..
Question 19
For measuring high values of alternating current with a dynamometer ammeter, we use a ………………
Question 20
Match List-I (Type of fault) with List-II (Type of protection) and select the correct answer using the code given below the lists: List-I A) External phase fault B) Faults between phases C) Phase to earth fault D) Overheating List-II 1) Differential protection 2) Earth fault relay 3) Over-current protection (inverse time delay o/c relay) 4) Thermal relay
Question 21
A hydraulic turbine having rated speed of 250 r.p.m. is connected to a synchronous generator. In order to produce power at 50 Hz, the number of poles required in the generator is
Question 22
What is the mean magnetic length of the magnetic circuit shown in Fig.?
Question 23
If the current through the operating coil of a moving-iron instrument is doubled, the deflecting torque becomes ……………..
Question 24
A 3-phase double layer stator winding has a coil span of 150 electrical degrees. Its coil span factor will be
Question 25
The effect of increasing beyond a certain limit may result in…………..
Question 26
A relay is connected to a 400/5 A current transformer and set for 1.5. The primary fault current of 2400 A needs a plug settling multiplier of
Question 27
The inductive susceptance of the circuit shown in Fig. is …………………
Question 28
A magnetic circuit carries a flux Φi in the iron part and a flux Φg in the air gap. Then leakage co-efficient is
Question 29
If the circuit shown in figure is connected to 120 V d.c., the current drawn by the circuit is …………….
Question 30
A permanent magnet moving coil ammeter is connected in 50 Hz a.c. circuit in which 5 A current is flowing. The meter will read
Question 31
A 10 kVA, 400 V/200 V single-phase transformer with 10% impedance, draws a steady short circuit current of
Question 32
In 36 slots, 4-pole, 3-phase alternator, the winding pitch is 7 slots. The electrical angle by which the winding is chorded is equal to
Question 33
Thermal runaway occurs when…………….
Question 34
In Fig., the co-efficient of coupling between the coils is……..
Question 35
The power taken by the circuit shown in figure is …………
Question 36
How many relays are used to detect inter phase fault of a three-line system?
Question 37
The power factor of the star-connected load shown in Fig. is………………….
Question 38
The current through ZL in the circuit so that maximum power can transfer to the load shown below will be _________.