<PRE><B>Question 62064</B>
P= 10 log Pout/Pin 
where Pin is the power input in watts and Pout is the power output in watts. If an amplififier has a power gain of 10 watts and the output power is 7 watts, find the input power. 
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10 = 10 log (7/Pin)
divide both sides by 10 to get:
1=log(7/Pin)
Convert to exponential form to get:
7/Pin=10^1
Solve for Pin to get:
Pin=7/10
Power Input = (7/10) watt
Cheers,
Stan H.
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