Because USA is cold country then india

1 Answer

Answer :

Because India uses 220-230volt 

In USA there they uses 110volt

Related questions

Description : for house hold purpose I require simple freequency converter for change 50HZ TO 60hz Power supply.?

Last Answer : You can purchase a frequency converter from ebay. Your item should arrive fairly quick.

Description : Why should be the frequency 50 Hz 60Hz only why not others like 45, 95 56 or anything , why should we maintain the frequency constant if so why it is only 50 Hz 60Hz?

Last Answer : We can have the frequency at any frequency you like, but than you must also make your own motors,high voltage transformers or any other equipment you want to use.We maintain the frequency at 50hz ... maintains a standard at 50 /60hz and the equipments are are made to operate at these frequency.

Description : Two alternators rated are 200 KW at 4% regulation, 400 KW 5% regulation operating in parallel at 50HZ , when supply 600 KW the new frequency is a) 50 b) 49 c) 51.3 d) 47.7

Last Answer : Ans: 47.7

Description : 4] In operating a 400hz transformer at 50Hz A. Only voltage is reduced in the same proportion as the frequency B. Only KVA rating is reduced in the same proportion as the frequency C. Both voltage and KVA rating are reduced in the same proportion as frequency D. None of the above

Last Answer : B. Only KVA rating is reduced in the same proportion as the frequency

Description : Derive the relationship between Synchronous speed (Ns) and frequency (f) of alternator.

Last Answer : Derivation of Relationship Between Synchronous speed (Ns) and Frequency (f) of Alternator: Let, Ns = rotor speed in rpm (synchronous speed) P = number of rotor poles f = frequency of emf in Hz ... complete cycle of emf is generated in the conductor as pair of poles passes it. Hence : 

Description : For 32" HDTV, is there a big difference between 60Hz and 120Hz?

Last Answer : refresh rate should not be relevant for any flat screen monitor. Hz values are only relevant for the old cathode ray tubes.

Description : A series combination of resistance 100 ohm and capacitance 50µf is connected in series to a 230 V, 50HZ supply. Calculate (i) Capacitive reactance (ii) Current (iii) Power factor (iv) Power consumed 

Last Answer : For RC series circuit

Description : A 3-phase 50HZ SCIM takes a power input of 30 KW at its full load speed of 1440 rpm. Total stator losses are 1 KW. The slip and rotor ohmic losses at full load are a) 0.02, 600 W b) 0.04, 580 W c) 0.04, 1160 W d) 0.04, 1200 W

Last Answer : Ans: 0.04, 1160 W

Description : 55 When a 400Hz transformer is operated at 50Hz its KVA rating is A. Reduced to 1/8 B. Increased 8 times C. Unaffected D. Increased 64 times

Last Answer : A. Reduced to 1/8

Description : A 400kW, 3-phase, 440V, 50Hz induction motor has a speed of 950 r.p.m. on fullload. The machine has 6 poles. The slip of the machine will be _______________. (A) 0.06 (B) 0.10 (C) 0.04 (D) 0.05

Last Answer : Ans: D N = Ns (1-S) 950 = 120 x 50 (1-S)/6 S = 0.05

Description : A 6-pole, 50Hz, 3-φ induction motor is running at 950 r.p.m. and has Cu loss of 5kW. The rotor input is (a) 10 kW (b) 95 kW (c) 100 kW (d) 9.5 kW 

Last Answer : s=(Ns-N)/Ns =(1000-950)/1000=0.05.rotor cu.loss= s*rotor inputwe have rotor cu loss=5kWtherefore, rotor input= rotor cu.loss/s                              =5kW/0.05                              =100 kW

Description : If a 3-phase, 400V, 50Hz, 4 pole induction motor is running at a slip of 5% then the relative speed of rotor field with respect to stator filed is:

Last Answer : If a 3-phase, 400V, 50Hz, 4 pole induction motor is running at a slip of 5% then the relative speed of rotor field with respect to stator filed is: zero

Description : A 3-phase, 4-pole, 50Hz induction motor runs at a speed of 1440 rpm. The rotating field produced by the rotor rotates at a speed of ________ rpm with respect to stator field. (A) 1500 (B) 0 (C) 1440 (D) 60

Last Answer : 0

Description : An 8-pole, 50Hz, three-phase induction motor is running at 705rpm and has a rotor copper loss of 5kW. Its rotor input is (A) 5.06 kW (B) 0.3 kW (C) 100 kW (D) 83.33 kW

Last Answer : An 8-pole, 50Hz, three-phase induction motor is running at 705rpm and has a rotor copper loss of 5kW. Its rotor input is 83.33 kW

Description : A 400kW, 3 -phase, 440V, 50Hz induction motor has a speed of 950 rpm on full load. The machine has 6 poles. The value of slip for the machine will be (A) 0.06 (B) 0.10 (C) 0.04 (D) 0.05

Last Answer : A 400kW, 3 -phase, 440V, 50Hz induction motor has a speed of 950 rpm on full load. The machine has 6 poles. The value of slip for the machine will be 0.05

Description : Write two application of the following motor (i) AC servo motor (ii) Stepper motor

Last Answer : (i)Applications of AC Servo Motor: 1. Computers 2. Robotics and toys 3. CD/DVD players 4. Textile industries 5. Instrument servos 6. Tracking and guidance system 7. Self- ... Laser cutters 20.Extruders 21.Engravers 22.Analytical and Medical instruments 23.Embroidery Machines 24.Packeging Machines

Description : Draw torque characteristics of shaded pole IM. State its any two applications.

Last Answer : Torque Characteristics of Shaded Pole IM: Applications of Shaded Pole Induction Motor: 1) Small Fans 2) Recording Instruments 3) Record Players 4) Gramophones 5) Toy motors 6) Photocopying machines 7) Small clocks 8) Hair dryers

Description : Draw and explain star delta starter for 3 phase induction motor

Last Answer : Star Delta Starter for 3 Phase Induction Motor:  Diagram Explanation: The stator winding of the motor which is designed for delta operation is connected in star during starting ... which connects stator windings in delta connection. Now each stator phase gets full line voltage VL.

Description : Explain construction and working of D.C. servomotor.

Last Answer : Construction and Working of D.C. Servo Motor: The D.C. motor that is used in servo-mechanism is called a D.C. servo motor. There are three main types of D.C. servo motor ... magnet materials used in PM motors eliminates the need for interpoles due to their excellent commutation characteristics. 

Description : Advantages of Short Pitch Coils for an Alternator

Last Answer : Advantages of Short Pitch Coils for an Alternator: (1) It gives better sinusoidal waveform by reducing the harmonic components. (2) It saves copper as length required for the connections is ... are illuminated, hysteresis & eddy current losses will be reduced and this increases the efficiency.

Description : State the function of following parts of slip ring induction motor: (i) Slip ring (ii) Fan (iii) Brushes (iv) Frame

Last Answer : Sr. No. Name of part Function 1 Slip ring 1) The rotor winding terminals are permanently connected to the slip rings. 2) Connects external resistance to rotor circuit through ... It provides mechanical support to the entire internal parts of motor. 2) Protects the inner parts.

Description : Draw and explain working of universal motor. Give two applications of universal motor.

Last Answer : Figure of Universal motor:   Operation of universal motor on A.C. and D.C. supply:   *A universal motor works on either DC or single phase AC supply. When the universal motor is ... , regardless of AC or DC supply, universal motor works on the same principle that DC series motor works.  

Description : Explain speed control method of 3 phase induction motor by the following methods: (1) Pole changing (2) Rotor resistance control (3) Stator voltage

Last Answer : 1) Pole Changing Method:  Synchronous speed is given by, From the above equation of synchronous speed, it can be seen that synchronous speed (and hence, running speed) can ... in voltage and consequently the speed decreases and vice versa. Ultimately speed depends on the supply voltage.

Description : Explain DOL starter used for 3 phase induction motor.

Last Answer : DOL Starter Used for 3 Phase Induction Motor: The direct online starter consist of overload relay (OLC), contactor, start-push button S1 (normally open), stop-push button S2 (normally ... The overload coil (OLC) protects the motor against overload and short circuit by opening the contact D.

Description : Compare squirrel cage induction motor and slip ring induction motor any four points.

Last Answer : Comparison Between Squirrel Cage Induction Motor and Slip Ring Induction Motor: Sr. No. Squirrel Cage Induction Motor Slip Ring Induction Motor 1 Rotor is in the form of short circuited bars ... drive e.g. Lathe machine. Used where high starting torque is required e.g. Lifts.

Description : State any four applications of 3 phase induction motor.

Last Answer : Applications of 3 Phase Induction Motor: 1) Lathes 2) Flour mills 3) Grinders 4) Centrifugal pumps 5) Drilling machines 6) Laundry washing machines 7) Wood working machines 8) Blowers 9 ... industries 38) For generators 39) Driving line shafts 40) For practical purposes in educational institutes.

Description : Explain the construction of three phase induction motor with neat diagram.

Last Answer : Construction of Three-phase Induction Motor: There are two main parts of the three phase induction motor:  i) Stator which is the stationary part  ii) Rotor which is the rotating ... slip-rings. In this rotor also the slots are not exactly parallel to the shaft but slightly skewed.