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Basic Electricity

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 unit of measurement of resistance?
Secondary cell
Ohms
The direction of the magnetic field
Grounding wire

2. What instrument measures voltage?
Choke
DC flows continuously in one direction and AC potential difference and current both change direction
Serial
Voltmeter

3. What is a way to classify wires and cables?
By their covering
Area and spacing of capacitor - static current in the capacitor(both A and B)
Energy
Volts

4. What is a property of inductors in electrical circuits?
It increases or decreases the potential difference of AC electricity - It is effective with almost no loss of power - It's use- cost is very low(All of the above)
Opposes any change in the current flowing in a circuit
How much potential difference can a material withstand before breaking down
Gauge number

5. What determines whether a spark can be produced?
Strength of the charge
Symbol
First digit
DC flows continuously in one direction and AC potential difference and current both change direction

6. Which of the following is a type of resistor?
Fixed - tapped - variable(all of the above)
Series circuit
Plastic - Rubber - Friction(all of the above)
75 Ohms

7. What is a common cause of static electricity in a shop?
Battery
Relationship between current and potential difference
Moving vehicles
Potential difference

8. What wire measurement is commonly used in the U.S.?
Heat
Unlike poles attract
Physical protection for conductors - Grounding for conductors - Concealment for conductors(all of the above)
American wire gauge(AWG)

9. What does a first band of white mean?
How much potential difference can a material withstand before breaking down
First digit is 9
Strength of the charge
Start with the band on the end and read to the center

10. What makes electrons flow?
Potential difference
Area and spacing of capacitor - static current in the capacitor(both A and B)
Cables
High dielectric and mechanical strength - tempurature and moisture resistance - flexible(All of the above)

11. Identify the blueprint symbol for resistors.
Chemical action
Ohms
Magnetic properties
--^V^V^V^---

12. What is a rigid metal conduit?
Symbol
Secondary cell
Physical protection for conductors - Grounding for conductors - Concealment for conductors(all of the above)
A magnetic field

13. What can permanently break down a capacitor?
5%
Breakdown voltage
Plastic - Rubber - Friction(all of the above)
A difference in potential energy

14. What makes electrons flow?
50 Ohms
Lifting devices - chucks and clutches - brakes and pulleys(all of the above)
Potential difference
Direction of: electric charge - magnetic field - force of the moving charge(all of the above)

15. How is the heat production measured in a resistor?
Potential difference - E*I - current times current change from point to point(all of the above)
Resistance increases as the conductor length increases
Resistance value can not be changed
Moving vehicles

16. What is a common form used in conductors?
Electrical resistance against the flow of current
Cables
Current flows in one direction - potential differences across a load does not change(Both A and B)
Bare - covered - insulated - stranded - cable(All of the above)

17. What do junction boxes protect?
Opposition to electrical current
Wire splices
First digit is 9
Series circuit

18. What is a conductor?
A material capable of carrying an electric current Silver - Copper - and Aluminum(Both A and C)
Current flows in one direction - potential differences across a load does not change(Both A and B)
Fixed - tapped - variable(all of the above)
10%

19. Which of the following materials is NOT a good conductor?
When current starts and stops flowing - when an inductor is in the circuit(Both A and B)
Porcelain
1/1000th of an inch
Fixed - tapped - variable(all of the above)

20. What is a switch that operates by electricity?
First digit
Grounding wire
Porcelain
Relay

21. Solve the equation: 35 volts / 0.70 amperes= ? ohms - to find resistance.
Energy
Moving vehicles
DC current
50 Ohms

22. What is the basic law of magnetic force?
It increases or decreases the potential difference of AC electricity - It is effective with almost no loss of power - It's use- cost is very low(All of the above)
Stranded
A material capable of carrying an electric current Silver - Copper - and Aluminum(Both A and C)
Unlike poles attract

23. How are the capacitors connected when the combined capacitance equals less than the lowest- value capacitor?
Porcelain
Ohms
Fixed - tapped - variable(all of the above)
Serial

24. If the fourth color band is gold - this means the measured value of the resistance is what percent of the marked value?
Stranded
Cell
5%
Magnetism produces a field and the field exerts force on a moving charge - every moving electrical charge produces a magnetic field - and the magnetic field is strong when the electrical charge is strong and moves rapidly(all of the above are true)

25. What is a common measure of wire diameter?
Gauge number
Solenoid and Relay(both A and B)
Bare - covered - insulated - stranded - cable(All of the above)
Fixed - Electrolytic - Variable(all of the above)

26. What is produced when an alternator rotates 360 electrical degrees through a magnetic field?
Strength of the charge
Amperes
Secondary cell
Alternating current

27. What are the common units of measurement for round and square conductor cross - sections?
Heat
Circular and square mills(Both A and B)
Choke
Resistance increases as the conductor length increases

28. How do you read resistor color codes?
Series circuit
A difference in potential energy
Start with the band on the end and read to the center
To prevent Physical - Chemical to wiring - to prevent damage to people and property(all of the above)

29. Given R=E / I and the following information - plug in the data and solve the problem for resistance. 1.5 volt walkman battery - 0.02 amps of current
Secondary cell
Mutual induction
75 Ohms
Insulation resistance and Dielectric strength(Both A and B)

30. What are the two generic methods to eliminate static electricity from metal objects?
Heat
When current starts and stops flowing - when an inductor is in the circuit(Both A and B)
Bonding and grounding
First digit

31. What is an electromagnet?
Composition of the resistor
Heat and current control(both a and c)
By their covering
A coil of wire that: carries current - has a magnetic field inside - and can have a bar of steel inside

32. What does a transformer transform?
A material capable of carrying an electric current Silver - Copper - and Aluminum(Both A and C)
The relationship of potential difference to current
1/1000th of an inch
Wire splices

33. What is the name for electrical resistance of insulation?
12 volts
Stranded
Insulation resistance
Resistance value can not be changed

34. What is the unit of measurement of potential difference?
Electromagnetic field
Grounding wire
Volts
Current flows in one direction - potential differences across a load does not change(Both A and B)

35. If the fourth color band is silver - this means the measured value of the resistance is what percent of the marked value?
Volts
Current flows in one direction - potential differences across a load does not change(Both A and B)
Battery
10%

36. What is a characteristic of a fixed resistor?
Resistance value can not be changed
Composition of the resistor
Common - not rechargable - gradually discharges when in storage(All of the above)
Plastic - Rubber - Friction(all of the above)

37. Where do the fingers point in both Left-Hand Rules?
1 watt
Relationship between current and potential difference
The direction of the magnetic field
Tolerence

38. What is voltage?
A difference in potential energy
Potential difference
Insulation resistance
Volts

39. The dry cell is what method for creating potential energy?
Chemical action
Area and spacing of capacitor - static current in the capacitor(both A and B)
Current change in a coil creates a magnetic change
1 watt

40. What information do the Left-Hand Rules provide?
Cells can be connected together to make a battery
Direction of: electric charge - magnetic field - force of the moving charge(all of the above)
Voltage
A coil of wire that: carries current - has a magnetic field inside - and can have a bar of steel inside

41. What is another name for an inductor?
To prevent Physical - Chemical to wiring - to prevent damage to people and property(all of the above)
Choke
50 Ohms
Volts

42. When does a DC circuit oppose current flow?
12 volts
When current starts and stops flowing - when an inductor is in the circuit(Both A and B)
The rate of doing work
Secondary cell

43. What type of circuit has one path of follow through a load?
The rate of doing work
Series circuit
First digit is 9
12 volts

44. What does static electricity do?
Evenly over the surface of a sphere and concentrated on points of objects(both A and C)
Bonding and grounding
Does not move
Grounding wire

45. What is the use of the electromagnet?
Bare - covered - insulated - stranded - cable(All of the above)
Lifting devices - chucks and clutches - brakes and pulleys(all of the above)
From the negative battery terminal to the positive terminal
Insulation resistance and Dielectric strength(Both A and B)

46. Which type of cell can be recharged?
Volts
The relationship of potential difference to current
Secondary cell
To prevent Physical - Chemical to wiring - to prevent damage to people and property(all of the above)

47. How are the capacitors connected when the combined capacitance equals a sum of all the capacitors?
Potential difference
Voltmeter
Parallel
How much potential difference can a material withstand before breaking down

48. What is resistance in electrical terms?
15 -000 ohms - 20%
How much potential difference can a material withstand before breaking down
Opposition to electrical current
1/1000th of an inch

49. What is the purpose of resistors in electrical circuits?
20%
Produce heat - light - or limit current to control it(all of the above)
Electromagnetic field
Purging

50. What do electrical charges need to cause a fire or explosion?
The direction the negative charge moves
To prevent Physical - Chemical to wiring - to prevent damage to people and property(all of the above)
Area and spacing of capacitor - static current in the capacitor(both A and B)
Means to maintain a potential difference - means to generate spark - spark in a flammable atmosphere(all of the above)