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📝 Electricity & Electrical Safety – Practice Quize (25 Questions)
1. Electricity is best defined as:
A) The flow of water through a conductor
B) The movement of electrons from one atom to another
C) A magnetic force without energy
D) Heat energy created by sunlight
Answer: B) The movement of electrons from one atom to another
2. Which material is a good conductor?
A) Wood
B) Glass
C) Copper
D) Rubber
Answer: C) Copper
3. Which material is a good insulator (non-conductor)?
A) Aluminum
B) Copper
C) Rubber
D) Steel
Answer: C) Rubber
4. Electric wires are made of:
A) Metal conductors covered with insulators
B) Plastic only
C) Wood and glass
D) Magnetic metals only
Answer: A) Metal conductors covered with insulators
5. Direct Current (DC) flows:
A) In one direction only
B) In two directions, alternating
C) At random intervals
D) Only through air
Answer: A) In one direction only
6. Which is an example of a Direct Current (DC) device?
A) Hair dryer plugged into wall
B) Flashlight
C) Table lamp
D) Electric file (corded)
Answer: B) Flashlight
7. Alternating Current (AC) is produced by:
A) Batteries
B) Chemical means
C) Mechanical generators
D) Static energy
Answer: C) Mechanical generators
8. AC changes direction how many times per second in the U.S.?
A) 30
B) 60
C) 100
D) 120
Answer: B) 60
9. The unit measuring pressure that pushes current through a conductor is:
A) Ampere
B) Volt
C) Ohm
D) Watt
Answer: B) Volt
10. Which is a typical household voltage in the U.S.?
A) 12V
B) 120V
C) 2400V
D) 5000V
Answer: B) 120V
11. The strength of an electric current is measured in:
A) Volts
B) Watts
C) Amperes
D) Ohms
Answer: C) Amperes
12. A milliampere is equal to:
A) 1/10 of an ampere
B) 1/100 of an ampere
C) 1/1,000 of an ampere
D) 10 amperes
Answer: C) 1/1,000 of an ampere
13. The unit that measures resistance in an electric current is:
A) Watt
B) Ohm
C) Volt
D) Amp
Answer: B) Ohm
14. The unit that measures how much energy is used in one second is:
A) Amp
B) Watt
C) Volt
D) Ohm
Answer: B) Watt
15. A kilowatt is equal to:
A) 100 watts
B) 500 watts
C) 1000 watts
D) 10,000 watts
Answer: C) 1000 watts
16. Which device melts or blows out to prevent excess current?
A) Circuit breaker
B) Fuse
C) Transformer
D) Conductor
Answer: B) Fuse
17. Which device shuts off automatically and can be reset?
A) Fuse
B) Battery
C) Circuit breaker
D) Transformer
Answer: C) Circuit breaker
18. Grounding provides:
A) More electricity to tools
B) A safe path for stray current
C) A way to increase resistance
D) Stronger wattage
Answer: B) A safe path for stray current
19. A three-prong plug provides:
A) Extra resistance
B) An additional ground for safety
C) More current to the appliance
D) Lower wattage
Answer: B) An additional ground for safety
20. What does a Ground Fault Interrupter (GFI) do?
A) Increases current
B) Detects leaks and interrupts the circuit to prevent shock
C) Stores electric charge
D) Changes AC into DC
Answer: B) Detects leaks and interrupts the circuit to prevent shock
21. Which organization certifies electrical appliance safety?
A) OSHA
B) FDA
C) UL (Underwriters Laboratories)
D) EPA
Answer: C) UL (Underwriters Laboratories)
22. Which safety practice is correct?
A) Pull appliances by the cord
B) Use multiple plugs in one outlet
C) Disconnect appliances when not in use
D) Insert hair pins into appliances if they stop working
Answer: C) Disconnect appliances when not in use
23. If you feel a shock when turning on an appliance, you should:
A) Continue using it
B) Dry your hands and try again
C) Stop using immediately and unplug it
D) Call the client to help hold it
Answer: C) Stop using immediately and unplug it
24. Electrotherapy treatments require:
A) One electrode
B) Two electrodes (positive and negative)
C) No electrodes
D) Only grounding wires
Answer: B) Two electrodes (positive and negative)
25. Which type of ultraviolet light is blocked by the ozone layer?
A) UVA
B) UVB
C) UVC
D) All of the above
Answer: C) UVC