Technician T5B: Metric prefixes and decibels
These are the 13 official questions in group T5B of the 2026–2030 Technician question pool, with the correct answer marked and a plain-English explanation of why it's right. The real exam asks one question from this group.
- T5B01Question 1
How many milliamperes is 1.5 amperes?
- A0.0000015 milliamperes
- B0.0015 milliamperes
- C1500 milliamperes Correct
- D1,500,000 milliamperes
Why: 1 A = 1,000 mA, so 1.5 A = 1,500 mA.
- T5B02Question 2
Which is equal to 1,500,000 hertz?
- A1500 kHz Correct
- B1500 MHz
- C15 GHz
- D150 kHz
Why: 1 kHz = 1,000 Hz, so 1,500,000 Hz = 1,500 kHz.
- T5B03Question 3
Which is equal to one kilovolt?
- AOne one-thousandth of a volt
- BOne hundred volts
- COne thousand volts Correct
- DOne million volts
Why: Kilo means 1,000, so a kilovolt is 1,000 volts.
- T5B04Question 4
Which is equal to one microvolt?
- AOne one-millionth of a volt Correct
- BOne million volts
- COne thousand kilovolts
- DOne one-thousandth of a volt
Why: Micro means one-millionth, so a microvolt is a millionth of a volt.
- T5B05Question 5
Which is equal to 500 milliwatts?
- A5 watts
- B0.5 watts Correct
- C500,000 watts
- D500,000,000 watts
Why: 500 mW ÷ 1,000 = 0.5 W.
- T5B06Question 6
Which is equal to 3000 milliamperes?
- A0.003 amperes
- B0.3 amperes
- C3,000,000 amperes
- D3 amperes Correct
Why: 3,000 mA ÷ 1,000 = 3 A.
- T5B07Question 7
Which is equal to 3.525 MHz?
- A0.003525 kHz
- B35.25 kHz
- C3525 kHz Correct
- D3,525,000 kHz
Why: 1 MHz = 1,000 kHz, so 3.525 MHz = 3,525 kHz.
- T5B08Question 8
Which is equal to 1,000,000 picofarads?
- A0.001 microfarads
- B1 microfarad Correct
- C1000 microfarads
- D1,000,000,000 microfarads
Why: 1 µF = 1,000,000 pF.
- T5B09Question 9
Which decibel value most closely represents a power increase from 5 watts to 10 watts?
- A2 dB
- B3 dB Correct
- C5 dB
- D10 dB
Why: Doubling power, from 5 to 10 W, is a 3 dB increase.
- T5B10Question 10
Which decibel value most closely represents a power decrease from 12 watts to 3 watts?
- A-1 dB
- B-3 dB
- C-6 dB Correct
- D-9 dB
Why: 12 W to 3 W is one quarter of the power, which is −6 dB.
- T5B11Question 11
Which decibel value represents a power increase from 20 watts to 200 watts?
- A10 dB Correct
- B12 dB
- C18 dB
- D28 dB
Why: 20 W to 200 W is ten times the power, which is +10 dB.
- T5B12Question 12
Which is equal to 28400 kHz?
- A28.400 kHz
- B2.800 MHz
- C284.00 MHz
- D28.400 MHz Correct
Why: 28,400 kHz ÷ 1,000 = 28.400 MHz.
- T5B13Question 13
Which is equal to 2425 MHz?
- A0.002425 GHz
- B24.25 GHz
- C2.425 GHz Correct
- D242.5 GHz
Why: 2,425 MHz ÷ 1,000 = 2.425 GHz.