Test your basic knowledge |

Transformers

Subject : engineering
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. A large amount of power wasted with the open-ended core






2. Transformer losses are classified as _____ and _____.






3. The output side it develops AC by electromagnetic mutual induction - Secondary voltage is induced in this coil






4. When an alternating current is applied to the high-voltage (H) winding of a transformer with no load on the secondary (X) winding - a small current - called the _____ current - flows in the primary.






5. A simple design has a core within each coil






6. Central magnetic core made of






7. To minimize ________ in transformer construction - the primary and secondary windings are placed on the same leg(s) of the core.






8. An abnormal connection of relative low resistance - whether made accidentally or intentionally - between two point of different potential in a circuit.






9. The magnetic lines of force that flow from the north pole of a magnet and return to the south pole.






10. It refers to the direction of current flow in a closed circuit.






11. Function of the dielectric oil






12. Anything above 600 volts is _____?






13. The turns of both windings are cut by the same flux; therefore the induced emf in each turn of both windings is the _____.






14. The loss of power required to reverse the core magnatism each time the current reverses. This loss is caused by friction between the molecules of iron as these particles are aligned first in one direction and the in the opposite direct as current dir






15. A single electrical circuit.






16. A partial or total local failure in the insulation or continuity of a conductor.






17. A transformer which when supplied from a constant potential source automatically maintans a constant current in its secondary circuit under varying conditions of load impedance. Used on series street light circuits.






18. A ___________ transformer is a continuously adjustable Autotransformer.






19. Divergence of the magnetic field causes this






20. The formula for the current related to voltage law






21. What does transformer efficiency mean?






22. _____ shows that the voltages across the windings of a transformer are directly proportional to the turns in each winding.






23. Determines if the transformer is a step up or step down transformer






24. ___________ is often used in laminated cores - increases electrical resistance which decreases eddy currents






25. The total numbre of lines or force issuing from a pole. (north or south)






26. How coils serve as the primary and secondary windings for an autotransformer






27. The transformer winding to which the load is connected is called the _____ winding.






28. An instrument used to measure electrical current.






29. If the transformer is used as a _____ transformer - the low voltage winding is the primary.






30. Modern; used to control filament circuit; replaced both the rheostat and choke coil; operated on the electromagnetic principle that if an iron core within or near a coil is saturated with magnetic flux by an independed source of direct current - the






31. Waste of power known as transformer loss - often produced by closed-ended core






32. The terminals of the low voltage winding are marked _____.






33. The capacity of a transformer is rated in ____ _____.






34. How a variable degree of core saturation is accomplished in a saturable reactor?






35. The output which can be delivered for the time specified at rated secondary voltage and rated frequency without exceeding the specified temperature limitations.






36. Copper loss is known as _____ loss.






37. Reference to a jumper or conductor - to or from a piece of electrical equipment.






38. The characteristic that requires energy to carry out the constant reorientation of the magnetic dipoles in the hysteresis loss






39. A choke coil uses this to induce current






40. Kind of wire is the secondary coil in a transformer






41. A transformer primary (H) that has 400 turns is wound to step the voltage down from 240 volts to 120 volts. The number or turns (TX) required in the secondary (X) winding is _____.






42. The input side that attaches to the AC supply it recieves the electrical energy or incoming voltage






43. The shape of the core of the transformer ensures a ______________ for the magnetic flux with maximum concentration within the core and minimum leakage of the air






44. The 3 types of transformer power loss






45. This is the most advanced and most efficient type of tansformer; it is commonly used in x-ray equipment






46. Refers to the transformer's ability to avoid power loss (heat)






47. Is concentrated in the metal core






48. Autotransformers are not safe when they supply a _____ voltage from a high voltage source.






49. The 4 types of transformer cores






50. The turns ratio between the windings (primary & secondary) of a transformer unless otherwise specified.






Can you answer 50 questions in 15 minutes?



Let me suggest you:



Major Subjects



Tests & Exams


AP
CLEP
DSST
GRE
SAT
GMAT

Most popular tests