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Sarkari MCQs Government Exam Question Bank
Question no. 25324

Given a power gain of 100 in an amplifier, its db gain equals ________________?

Select your answer for: Given a power gain of 100 in an amplifier, its db gain equals ________________?
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Answer: B. 20 db

Explanation

Decibel power gain is calculated using ten times the logarithm base ten of power ratio. The logarithm base ten of one hundred equals two precisely. Multiplying ten by two yields a total decibel gain of twenty dB. Decibels provide a logarithmic scale for expressing power and voltage ratios conveniently. Power gain compares output power level directly to input power level. Logarithmic scales compress wide numerical ranges into manageable values for engineers.

Audio amplifier specifications list power gains and frequency responses in decibels. Telecommunication engineers use decibel units to calculate signal loss across transmission lines. Sound pressure levels are measured in decibels to match human hearing perception. Ten decibels corresponds to a power gain ratio of ten rather than one hundred. Forty decibels represents a much larger power gain ratio equal to ten thousand. None of the above is wrong because twenty decibels is the correct mathematical result.

Subject
Engineering
Category
Electrical Engineering
Topic
—
Difficulty
medium

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