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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 does static electricity do?
DC current
By their covering
Does not move
Mutual induction

2. What is the purpose of resistors in electrical circuits?
Volts
75 Ohms
Produce heat - light - or limit current to control it(all of the above)
Current flows in one direction - potential differences across a load does not change(Both A and B)

3. What does an object have if a magnetic field acts on it?
Unlike poles attract
Magnetic properties
Lifting devices - chucks and clutches - brakes and pulleys(all of the above)
High dielectric and mechanical strength - tempurature and moisture resistance - flexible(All of the above)

4. What does Ohm's Law represent?
Relationship between current and potential difference
Potential difference
Cell
High dielectric and mechanical strength - tempurature and moisture resistance - flexible(All of the above)

5. What is a characteristic of insulators?
High dielectric and mechanical strength - tempurature and moisture resistance - flexible(All of the above)
Electrical resistance against the flow of current
Symbol
Gauge number

6. Which material has the lowest resistance at ordinary temperatures?
First digit
Heat
Silver
Stores electrical charge

7. What is the basic law of magnetic force?
Energy
Resistance value can not be changed
A difference in potential energy
Unlike poles attract

8. What do junction boxes protect?
Does not move
Wire splices
Series circuit
Parallel circuit

9. What is another name for an inductor?
Electromagnetic field
Choke
Solenoid and Relay(both A and B)
Battery

10. What is an electromagnet?
From the negative battery terminal to the positive terminal
High resistance
A coil of wire that: carries current - has a magnetic field inside - and can have a bar of steel inside
Strength of the charge

11. Given E=I X R and the following information - plug in the data and solve the problem for voltage. 0.015 ohms - 800 amps of current
20%
12 volts
A material capable of carrying an electric current Silver - Copper - and Aluminum(Both A and C)
Volts

12. What does a first band of white mean?
Tolerence
When current starts and stops flowing - when an inductor is in the circuit(Both A and B)
First digit is 9
Area and spacing of capacitor - static current in the capacitor(both A and B)

13. When reading resistance color codes - what does the fourth band indicate?
Tolerence
Wire splices
Symbol
Evenly over the surface of a sphere and concentrated on points of objects(both A and C)

14. In most applications - what remains constant if the current remains constant and flows in one direction?
Stranded
Electromagnetic field
Secondary cell
Heat

15. What is the type of cable composed of many fine wires?
Composition of the resistor
American wire gauge(AWG)
Stranded
Alternating current

16. To what measurement do the conductor mills refer?
1/1000th of an inch
Voltage
Opposition to movement of free electrons
Amperes

17. How do you read resistor color codes?
1 watt
Start with the band on the end and read to the center
Heat
Produce heat - light - or limit current to control it(all of the above)

18. When reading resistance color codes - what does the first band indicate?
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)
How much potential difference can a material withstand before breaking down
First digit
Strength of the charge

19. 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
Start with the band on the end and read to the center
75 Ohms
Resistance value can not be changed
Direction of: electric charge - magnetic field - force of the moving charge(all of the above)

20. What is insulation resistance?
DC current
Fixed - Electrolytic - Variable(all of the above)
Relationship between current and potential difference
Electrical resistance against the flow of current

21. If the fourth color band is missing - this means the measured value of the resistance is what percent of the marked value?
20%
Electrical resistance against the flow of current
Porcelain
Cables

22. What wire measurement is commonly used in the U.S.?
American wire gauge(AWG)
Heat
Relationship between current and potential difference
The direction of the magnetic field

23. What type of circuit has two or more paths for current to follow?
First digit
A coil of wire that: carries current - has a magnetic field inside - and can have a bar of steel inside
Parallel circuit
1 watt

24. How is the heat production measured in a resistor?
The direction the negative charge moves
Two
Opposition to electrical current
Potential difference - E*I - current times current change from point to point(all of the above)

25. What are the two generic methods to eliminate static electricity from metal objects?
First digit
Strength of the charge
Direction of: electric charge - magnetic field - force of the moving charge(all of the above)
Bonding and grounding

26. Where does the thumb point in both Left-Hand Rules?
Current change in a coil creates a magnetic change
Bare - covered - insulated - stranded - cable(All of the above)
Battery
The direction the negative charge moves

27. Identify the blueprint symbol for capacitors.
Symbol
Volts
Heat and current control(both a and c)
How much potential difference can a material withstand before breaking down

28. What does resistance produce?
Opposes any change in the current flowing in a circuit
Heat
Composition of the resistor
50 Ohms

29. Which of the following materials is NOT a good conductor?
The relationship of potential difference to current
Volts
Porcelain
Heat

30. What is the difference between AC and DC?
A material capable of carrying an electric current Silver - Copper - and Aluminum(Both A and C)
Silver
DC flows continuously in one direction and AC potential difference and current both change direction
20%

31. When does a DC circuit oppose current flow?
10
When current starts and stops flowing - when an inductor is in the circuit(Both A and B)
Direction of: electric charge - magnetic field - force of the moving charge(all of the above)
Heat

32. A resistor is color coded brown - green - orange. What is its resistance?
15 -000 ohms - 20%
Does not move
Chemical action
To prevent Physical - Chemical to wiring - to prevent damage to people and property(all of the above)

33. What is a common cause of static electricity in a shop?
Direction of: electric charge - magnetic field - force of the moving charge(all of the above)
Heat
Moving vehicles
Use an effect to produce another effect

34. What are the common units of measurement for round and square conductor cross - sections?
Heat
When current starts and stops flowing - when an inductor is in the circuit(Both A and B)
Circular and square mills(Both A and B)
First digit

35. What do we call the process of replacement of vapor above a liquid with a nonflammable gas?
Opposition to movement of free electrons
Evenly over the surface of a sphere and concentrated on points of objects(both A and C)
Purging
Unlike poles attract

36. Identify the general blueprint symbol for inductors.
Symbol
Start with the band on the end and read to the center
Electrical resistance against the flow of current
Lifting devices - chucks and clutches - brakes and pulleys(all of the above)

37. What is the measure of potential difference?
Volts
Bare - covered - insulated - stranded - cable(All of the above)
The direction the negative charge moves
Electromagnetism

38. What is the fundamental property of insulators?
Opposes any change in the current flowing in a circuit
Volts
Insulation resistance and Dielectric strength(Both A and B)
Battery

39. What is a conductor?
Voltmeter
Means to maintain a potential difference - means to generate spark - spark in a flammable atmosphere(all of the above)
A material capable of carrying an electric current Silver - Copper - and Aluminum(Both A and C)
Ability to store an electric charge

40. What is capacitance in electrical terms?
Ability to store an electric charge
Voltmeter
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)
Breakdown voltage

41. What is an arrangement of materials that create a potential difference by chemistry?
Resistance value can not be changed
Breakdown voltage
Cell
DC flows continuously in one direction and AC potential difference and current both change direction

42. What is needed for electric heating elements and the filaments of light bulbs?
Opposition to movement of free electrons
High resistance
Wire splices
How much potential difference can a material withstand before breaking down

43. What is the unit of measurement of electrical current?
Amperes
Opposition to electrical current
Strength of the charge
By their covering

44. What is a property of inductors in electrical circuits?
Composition of the resistor
Insulation resistance and Dielectric strength(Both A and B)
Ability to store an electric charge
Opposes any change in the current flowing in a circuit

45. Which type of cell can be recharged?
Lifting devices - chucks and clutches - brakes and pulleys(all of the above)
Secondary cell
Electromagnetism
Cables

46. What does a transformer transform?
The relationship of potential difference to current
By their covering
Voltmeter
Secondary cell

47. What is true about a dry cell?
From the negative battery terminal to the positive terminal
How much potential difference can a material withstand before breaking down
Common - not rechargable - gradually discharges when in storage(All of the above)
Purging

48. What does a moving charge produce?
A magnetic field
Volts
Area and spacing of capacitor - static current in the capacitor(both A and B)
Strength of the charge

49. What makes electrons flow?
Potential difference
Purging
Voltage
Electrical resistance against the flow of current

50. What is 'difference in potential(potential difference) - per unit of charge - between two points'?
Direction of: electric charge - magnetic field - force of the moving charge(all of the above)
Potential difference - E*I - current times current change from point to point(all of the above)
Stranded
Voltage