Test your basic knowledge |

DC Theory

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 hazard of pouring water into battery acid 'electrolyte'?

Warning: Invalid argument supplied for foreach() in /var/www/html/basicversity.com/show_quiz.php on line 183

2. Power is measured with a...
Until the victim receives medical attention.
Clean water.
Wattmeter.
Flush thoroughly with water.

3. What is the total voltage of four 12-volt batteries connected in series?
It must prevent ignition of surrounding methane atmosphere.
48 volts
Current.
Flush thoroughly with water.

4. What is the total resistance of four 15-ohm resistors connected in series?
60 ohms.
Ohms.
Current that flows in only one direction.
After charging

5. Which of the following stays the same in all parts of a series circuit?
Distance.
The movement of electrons in a circuit.
Current
Resistance.

6. What is the flow of electrons in a conductor?
In series.
Current.
In series.
A. Total resistance is less than the smallest resistor.

7. Which of the following is a requirement of an explosion-proof enclosure?
36 volts.
It must prevent ignition of surrounding methane atmosphere.
4.8 ohms
Treat for physical shock.

8. How long should treatment for shock be continued?
Direct current.
Better speed control on motors.
Until the victim receives medical attention.
Distance.

9. Voltage in a parallel circuit...
Wattmeter.
Stays the same.
Until the victim receives medical attention.
Reverse.

10. The longer the conductor - the greater the...
Ohms.
Direct current.
Resistance.
Compound-wound and shunt-wound.

11. The first step in treating a chemical burn - such as one caused by battery acid - is to...
Flush thoroughly with water.
Watts.
Repel each other.
36 volts.

12. What is the total resistance of three 16-ohm resistors connected in series?
Until the victim receives medical attention.
400 ampere-hours.
48 ohms.
Treat for physical shock.

13. What is the equivalent resistance of two 8-ohm resistors connected in parallel?
4.0 ohms.
Heat
Current
Flush thoroughly with water.

14. How many watts are in one horsepower?
Distance.
Ammeter.
A bi-directional device that can pass current in either direction.
746 watts.

15. What voltage would be required to force 10 amps through a 50-ohm resistor?
Wattmeter.
It must prevent internal explosions.
There is a hazard of blowing the contents back into your face - 'explosive reaction'.
500 volts.

16. The explosive gas that is generated when a battery is charging is...
Distance.
Hydrogen.
Hydrometer.
Voltmeter.

17. How many kilowatts are used to develop 50 horsepower?
Resistance.
E=IR.
The opposition to flow of electrons in a circuit.
37.3 kilowatts

18. What is the equivalent resistance of two 16-ohm resistors connected in parallel?
Stays the same.
Better speed control on motors.
400 ampere-hours.
8 ohms.

19. Resistance is measured with a...
Hydrometer.
Current
Ohmmeter.
Better speed control on motors.

20. What voltage would be required to force 10 amps through a 20-ohm resistor?
Ohms.
A counter-EMF.
36 volts.
200 volts

21. Chemical burns caused by battery acid should be washed with clean water for at least...
It must prevent internal explosions.
15 minutes.
Ventilation.
Ammeter.

22. Voltage is measured with a...
Voltmeter.
8 ohms.
Flush the burn the clean water.
Hydrogen.

23. What is the rate that work is done or heat is dissipated?
Power.
Resistance.
Decrease.
The opposition to flow of electrons in a circuit.

24. What is the total voltage of eight 12-volt batteries connected in series?
400 ampere-hours.
In parallel.
No.4 AWG.
96 volts.

25. Define resistance...
Repel each other.
Higher current with voltage remaining the same.
Current that flows in one direction only.
The opposition to flow of electrons in a circuit.

26. The best insulator against the lines of magnetic force is...
Distance.
Reverse.
75 volts.
There is a hazard of blowing the contents back into your face - 'explosive reaction'.

27. The minimum allowable size of trailing cable on DC-powered mobile haulage equipment is...
Stays the same.
Flush the burn the clean water.
No.4 AWG.
It must prevent internal explosions.

28. The most common reason that solid state devices fail is...
60 ohms.
Heat
15 minutes.
Watts.

29. Which current flows in only one direction?
Attract each other.
In parallel.
Ventilation.
Direct current.

30. Unlike poles of a magnet will...
Stays the same.
Stays the same.
Treat for physical shock.
Attract each other.

31. What must be provided at underground battery charging stations?
Ventilation.
It must prevent ignition of surrounding methane atmosphere.
Hydrometer.
Flush the burn the clean water.

32. The instrument used to check the electrolyte of a battery is a...
Hydrometer.
Flush thoroughly with water.
Less than the resistance of either resistor.
It must prevent internal explosions.

33. How must two 12-volt batteries be connected in order to increase the current capacity?
Heat
In parallel.
60 ohms.
Resistance.

34. Trailing cable on DC-powered mobile haulage equipment must be at least...
Amperes.
60 ohms.
No.4 AWG.
Current

35. Resistors are rated in ohms and...
E=IR.
6 volts.
Compound-wound and shunt-wound.
Watts.

36. What is the first step in treating a chemical burn of the eye?
60 ohms.
Flush the burn the clean water.
Amperes.
Hydrogen.

37. The unit of measurement of resistance is?
In parallel.
Power.
Ohms.
37.3 kilowatts

38. Not true about electrical shocks?
Burns will appear only at the point where contact is made to the energized circuit.
Repel each other.
Until the victim receives medical attention.
Clean water.

39. Define direct current...
Hydrogen.
Current that flows in only one direction.
1.260 to 1.280.
4.8 ohms

40. Define direct current...
500 volts.
Current that flows in one direction only.
Heat
48 ohms.

41. What is the total voltage of four 9-volt batteries connected in a series?
Stays the same.
Resistance.
Reverse.
36 volts.

42. You have three 9-volt batteries. How should you connect them in order to supply 27 volts?
96 volts.
It must prevent internal explosions.
Decrease.
In series.

43. A triac is?
A bi-directional device that can pass current in either direction.
Flush the burn the clean water.
No.4 AWG.
It must prevent internal explosions.

44. What is Ohm's Law?
Direct current.
E=IR.
Wattmeter.
Hydrometer.

45. The unit of measurement of power is...
Watts.
Reverse.
Flush thoroughly with water.
Distance.

46. The unit of measurement of current is...
The movement of electrons in a circuit.
Less than the resistance of either resistor.
Ohmmeter.
Amperes.

47. Current is measured with a (an)...
Better speed control on motors.
6 volts.
The movement of electrons in a circuit.
Ammeter.

48. The combined resistance of two resistors in parallel is...
It must prevent internal explosions.
Series-wound.
500 volts.
Less than the resistance of either resistor.

49. What is the equivalent resistance of an 8-ohm and a 12-ohm resistor connected in parallel?
500 volts.
Repel each other.
4.8 ohms
Current.

50. What voltage is required to force 5 amps through a 15-ohm resistor?
Direct current.
Amperes.
36 volts.
75 volts.