How many decibels are related to a 90% decrease in imaging power?

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Multiple Choice

How many decibels are related to a 90% decrease in imaging power?

Explanation:
Decibels quantify how a power ratio behaves on a logarithmic scale, using the formula dB = 10 log10(P2/P1). A 90% decrease means the power is reduced to 10% of its original value, so P2/P1 = 0.1. Plugging that in gives dB = 10 log10(0.1) = 10(-1) = -10 dB. So a -10 dB change corresponds to a tenfold (90%) decrease in imaging power. The other values would correspond to much smaller or much larger changes in power.

Decibels quantify how a power ratio behaves on a logarithmic scale, using the formula dB = 10 log10(P2/P1). A 90% decrease means the power is reduced to 10% of its original value, so P2/P1 = 0.1. Plugging that in gives dB = 10 log10(0.1) = 10(-1) = -10 dB. So a -10 dB change corresponds to a tenfold (90%) decrease in imaging power. The other values would correspond to much smaller or much larger changes in power.

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