# The Decibel MCQ’s

This set of Electronic Devices & Circuits Multiple Choice Questions & Answers (MCQs) focuses on “The Decibel”.

1. What is the corresponding change in level for a factor of 10 change in power?
a) 100dB
b) 20dB
c) 10dB
d) 0.1dB

2. What is the corresponding change in level for a factor of 10 change in amplitude?
a) 100dB
b) 20dB
c) 10dB
d) 0.1dB

3. What is the symbol of a decibel?
a) dB
b) Db
c) DB
d) db

4. What is the value of voltage gain in decibels if Voutput = 20V and Vinput = 15V?
a) 1.75dB
b) 2.28dB
c) 1.37dB
d) 2.48dB

5. How is the power ratio corresponding to 12dB change in level?
a) 16.38
b) 14.24
c) 15.85
d) 12.88

6. The symbols dBA, dBB and dBC are used for to estimated human ear’s reaction to sound.
a) True
b) False

7. What is the value of power gain in decibels if Poutput = 250W and Pinput = 100W?
a) 2.48dB
b) 3.98dB
c) 1.78dB
d) 3.54dB

8. What is dBFS used to measure in terms of decibels?
a) Peak amplitude of a signal
b) Power relative to 1mW
c) Amplitude of a signal
d) Volume unit

9. What is dBTP used to measure in terms of decibels?
a) Peak amplitude of a signal
b) Power relative to 1mW
c) Amplitude of a signal
d) Volume unit

10. What is dBm used to measure in terms of decibels?
a) Peak amplitude of a signal
b) Power relative to 1mW
c) Amplitude of a signal
d) Volume unit