- #1
Mohamed Abdul
Homework Statement
1. A sinusoidal source with RMS voltage V = 11Volts across a resistor R = 50Ohms, determine the dBm value. Hint: you will first have to determine the power delivered and then check the formula for dBm calculations.
2. A type of coaxial cable has a loss of 12dB/100m at some frequency. Determine the ratio of the input voltage to the output voltage for 100m of this cable.
Homework Equations
dBm = 10logbase10(P/1mW)
dB = 20logbase10(V/Vo)
The Attempt at a Solution
For the first one, I found power to be 2.42. I then put 10logbase10(2.42/1000) into my calculator and got -26.16.
For the second 1 I set 12 = 20logbase(V/Vo), divided both sides by 12, and got .6 = logbase10(V/Vo). I then took 10 to the .6 power and got 3.98.
I'm just wondering if my math is right; getting a negative answer for the first one doesn't seem right to me, and I'm unsure if I did the log properly for the second one.