Choose the correct answer from the given alternative: 1. In an ideal transformer, (a) windings have no resistance (c) core has no losses (b) core has infinite permeability (d) all of the above. 2. The primary and secondary induced e.m.fs. El and E2 in a two-winding transformer are always: (a) equal in magnitude (b) in-phase with each other (c) antiphase with each other (d) determined by load on transformer secondary. 3. In relation to a transformer, the ratio 20: 1 indicates that (a) there are 20 turns on primary one turn on secondary (b) secondary voltage is 1/20th of primary voltage (c) primary current is 20 times greater than the secondary current. (d) for every 20 turns on primary, there is one turn on secondary. 4. A transformer has negative voltage regulation when its load power factor is: (a) zero (b) lagging. (c) leading (d) unity

Choose the correct answer from the given alternative: 1. In an ideal transformer, (a) windings have no resistance (c) core has no losses (b) core has infinite permeability (d) all of the above. 2. The primary and secondary induced e.m.fs. El and E2 in a two-winding transformer are always: (a) equal in magnitude (b) in-phase with each other (c) antiphase with each other (d) determined by load on transformer secondary. 3. In relation to a transformer, the ratio 20: 1 indicates that (a) there are 20 turns on primary one turn on secondary (b) secondary voltage is 1/20th of primary voltage (c) primary current is 20 times greater than the secondary current. (d) for every 20 turns on primary, there is one turn on secondary. 4. A transformer has negative voltage regulation when its load power factor is: (a) zero (b) lagging. (c) leading (d) unity

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

See similar textbooks

Similar questions

A single-phase transformer has 180 and 45 turns, respectively, on its primary and secondary windings. The corresponding resistances are 0.2422 and 0.076 S2, respectively. Determine the equivalent resistance a. in primary terms, and b. in secondary terms.
Find the elements of the equivalent circuit relative to the secondary of a single-phase transformer. The no-load voltages in the primary and secondary circuits are 200,400 volts, respectively, at a frequency of 50 Hz The primary no-load current at voltage 200 equals 0.7 amps and pulp losses equal to 70 watts Primary resistance and reactance 3.2 , 1.25 In order, the reactance of the resistance and the coil 0.6 , 0.7 Then draw the equivalent circle, explaining the values
In no load phasor diagram of practical transformer, the magnetizing current is with flux 4. In phase 90 Degree out of phase Lagging by 60 Degrees Leading by 60 Degrees
Ideal transformer with primary of 200 turns and secondary of 100 turns . The primary is connected to 220 V , 50 Hz supply . Secondary is connected to a load of 500 W at unity power factor . Determine : a ) Secondary voltage . b ) Load current . c) Input current to primary . d) Load impedance. e) Input impedance on primary.
Core losses of a single phase 440/240 V, 24 kVA, 50 Hz transformer is 750 W. Maximum efficiency of the transformer is 90% at 15 kVA load and a certain power factor. Find the efficiency of the transformer at the same power factor and full load.
How does the coupling factor affect the primary and secondary voltages? For example if the turns ratio in my transformer is 1:2 and the Vin is 10V, the voltage on the primary side is 10V and the voltage on the secondary side is 20V when the coupling factor (k) is 1. What will the primary and secondary voltages be if the coupling factor becomes 0.5?
When the transformer is loaded in a balanced fashion up to its nominal rating (10 MVA), calculate the high side line-to-line phasor voltages (ab, bc, ca). and low side phasor voltages both line-to-line and line-to-neutral (ab, bc, ca, a, b,c). as a reference for calculations the low side A line to neutral voltage is 7620V at an angle of 0 degrees when the transformer is at rated power. The transformer has the following characteristics: V: 138kV delta high side/ 13.2 kV wye low side 9% impedance X/R ratio of 20
Q5:Choose the correct answer from the given alternatives (answer five only) 1.In an ideal transformer, (a) windings have no resistance (b) core has infinite permeability (d) all of the above. (c) core has no losses 2. The primary and secondary induced e.m.fs. El and E2 in a two-winding transformer are always: (a) equal in magnitude (b) in-phase with each other (c) antiphase with each other (d) determined by load on transformer secondary. 3. In relation to a transformer, the ratio 20 : 1 indicates that (a) there are 20 turns on primary one turn on secondary (b) secondary voltage is 1/20th of primary voltage (c) primary current is 20 times greater than the secondary current. (d) for every 20 turns on primary, there is one turn on secondary. 4. A transformer has negative voltage regulation when its load power factor is: (a) zero (b) lagging. (d) unity (c) leading
b) The parameters of the transformer equivalent circuit are given bellow, Primary =1290. Secondary winding turns =130. The resistance of the primary winding =0.2 O. The resistance of the secondary winding =0.06 N. The leakage reactance of the primary winding =1.47 Q. The leakage reactance of the secondary winding =0.07 Q. using the above parameter values, referred to the primary winding, determine (a) Equivalent resistance, (b) Equivalent reactance, (c) Equivalent impedance and (d) The phase angle of the impedance.
In a transformer that has 10 times more turns on the secondary side (side 2) than on the primary side (side 1), the magnitude of the voltage/EMF across the windings on the secondary side, E₂ will be... O a.... 10 times lower than the voltage/emf on the primary side, E₁. O b.... the same as the voltage/emf on the primary side. O c.... always zero regardless of the voltage on the primary side, E₁. O d.... 10 times higher than the voltage/emf on the primary side, E₁.
figure the S-parameters for an ideal transformer with turn ratio N = N1:N2 where N1 is the no.of turns of the primary winding and N2 is the no. of turns of the secondary winding.