Test your basic knowledge |

Subjects : science, 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. What is the first step to be followed in aiding a victim of electrical shock?






2. The combined capacitance of two capacitors in parallel is...






3. Alternating current may be defined as...






4. What value of voltage will be measured from phase-to-phase - in a wye-connected secondary - if 2 -300 volts is measured from phase-to-ground?






5. High voltage is used to transmit power over long distances...






6. Compared to the secondary of a loaded - step-down transformer - the primary has...






7. Using a 10:1 ratio transformer - the terminals on the secondary side or lower voltage side would be marked...






8. What is the danger when working around capacitors?






9. A transformer with 3000 turns in the primary winding has a primary voltage of 4 -800 volts and a secondary voltage of 240 volts. How many turns are in the secondary winding?






10. A transformer has 1 -600 turns in the primary and 400 turns in the secondary. The primary voltage is 2 -400 volts. What is the secondary voltage?






11. Find the turns ratio of a single-phase transformer with the following values: Primary power of 5KW - secondary current of 100 amps - and primary voltage of 250 volts.






12. Not true about AC power?






13. Define alternating current...






14. Not an acceptable method for the installations of surface transformers?






15. Under fault conditions - the grounding resistor in a high voltage circuit limits the voltage drop in the grounding circuit external to the resistor to not more than...






16. Should a ground fault occur - what device can be installed to limit the current in the neutral of a three-phase AC system?






17. When connecting 3 single-phase transformers into a three-phase system - which of the following is NOT required for the single-phase transformers.






18. Operating coils - motors - transformers - relays and solenoids depend upon...






19. Two 10-hp induction motors are operating on 460 volts AC. One motor is connected by single- phase; the other is connected in three-phase. The three-phase will...






20. A solenoid coil is...






21. A transformer with 10 turns on the primary coil and 100 turns on the secondary is classified as...






22. If 13 -200 volts are measured from phase-to-phase across a wye-connected secondary - What is the phase-to-ground voltage?






23. A wound-rotor induction motor has all the following EXCEPT...






24. Three-phase AC underground cables must be provided with overcurrent protection using a...






25. When not connected to a load - the secondary leads of a current transformer should be...






26. A transformer has 2000 turns in the primary and 500 turns in the secondary. The primary voltage is 3 -200 volts. What is the secondary voltage?






27. The property of an electrical circuit that opposes any change in voltage is called...






28. How can you tell if a victim receiving mouth-to-mouth resuscitation is getting air into the lungs?






29. What position of a selector switch using a voltmeter would you select to check a 120-volt AC circuit to obtain the most accurate reading?






30. All transformers step voltage up or down by...






31. If the conductors of a balanced - three-phase circuit pass through a current transformer - how many amps will flow in the transformer?






32. The minimum allowable size for trailing cables for mobile haulage equipment powered by alternating current is...






33. Surface transformer installations - unless constructed to eliminate shock hazards - must be installed at least...






34. The property of an electric circuit that opposes any change in current is called...






35. A transformer with 1 -500 turns in the primary winding has a primary voltage of 2 -400 volts and a secondary voltage of 120 volts. How many turns are in the secondary winding?






36. When troubleshooting a circuit with a bank of capacitors - what precautions must be taken?






37. If you use a clamp-on ammeter or tong tester around all three-phase wires of an energized three- phase circuit simultaneously...






38. The primary leads of a single-phase transformer should be connected to the...






39. The following motor leads are brought out of a 3-phase motor (T1 - T2 - T3 - T4 - T5 - T6). This motor is probably for...






40. What should the duty rating of a grounding resistor be?






41. If a voltmeter were placed between two phase leads of a three-phase 480-volt system - the meter would read...






42. A transformer with a 1:1 ratio is usually a (an)...






43. AC voltage is raised or lowered by means of...






44. If current were flowing through a grounding resistor in a 440-volt - resistance-grounded system - this would probably be because...






45. The transformer used only to measure voltage is a...






46. The most reliable method to use to determine whether or not the heart has stopped is by checking the...


47. A burn causing a blister is classified as a...






48. The standard frequency of power supplied by the power company is...






49. What type motor is a wound-rotor induction motor?






50. Current transformers - or CT's - are used to...