What is the approximate decibel change when a signal's intensity is reduced to one half?

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Multiple Choice

What is the approximate decibel change when a signal's intensity is reduced to one half?

Explanation:
Decibels express relative power changes on a logarithmic scale. For power (intensity), a change by a factor of two corresponds to 10 log10(2) ≈ 3.01 dB. If the signal’s intensity is reduced to one half, the ratio is 0.5, so the change is 10 log10(0.5) ≈ -3.01 dB. That means about a 3 dB decrease. The other numbers would correspond to larger decreases: -6 dB for a quarter of the power, -9 dB for one-eighth, and -12 dB for one-sixteenth.

Decibels express relative power changes on a logarithmic scale. For power (intensity), a change by a factor of two corresponds to 10 log10(2) ≈ 3.01 dB. If the signal’s intensity is reduced to one half, the ratio is 0.5, so the change is 10 log10(0.5) ≈ -3.01 dB. That means about a 3 dB decrease. The other numbers would correspond to larger decreases: -6 dB for a quarter of the power, -9 dB for one-eighth, and -12 dB for one-sixteenth.

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