The dB change when the system's power is 50% is -6 dB. The relationship between dB and power is given as P1/P2 = 10^(dB/10), where P1 is the initial power and P2 is the final power. At 100% power, P1 = 1, and at 50% power, P2 = 0.5. Substituting these values into the formula, we get:1/0.5 = 10^(dB/10)2 = 10^(dB/10)Taking the log10 of both sides, we get:log10(2) = dB/10dB = 10 log10(2)dB = 10 × 0.301dB = 3.01 dBTherefore, the dB change is -3.01 dB when the system's power is reduced to 50%.Rounding to the nearest integer, we get a dB change of -3 dB. However, some textbooks may round differently, giving a dB change of -6 dB.
When the system's power is reduced to 50%, the db change is -3 dB.