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I is NOT the the square root of power. It is the square root of (power
divided by R) You first have to divide the power by the resistance THEN take the square root. And E=I x R not I x I x R Back to Ohms Law --see URL: http://www.angelfire.com/pa/baconbacon/page2.html and AC RMS power is the same as DC power. Provided the circuit has no inductance and capacitance and RMS values are used -- see OHMS LAW URL above and URL: http://www1.jaycar.com.au/images_uploaded/ohmpower.pdf About now I think you are putting me on, so the old Elmer is exit stage left. Elmer E Ing ------------------------------------------------ "Richard" anom@anom wrote in message ... "Elmer E Ing" wrote in message news:VM_Ua.12050$ff.5596@fed1read01... Oh boy -- lets assume an antenna is totally resistive -- 50 ohms or better still a dummy load of 50 ohms that exhibits no inductance or capacitance. Now since Power in watts = I squared R where I is the current and R is a pure 50 ohm resistance transpose and solve for I = square root of P over R I get about 4.9 amperes RF current now E=I times R so 4.9 times 50 = 244 volts RF volts That's what you should see at the antenna. Try that on old knucklehead. With any inductive reactance or capacitive reactance --- different ball game. Gurus check my math please RF power is not electrical power. As audio power is not electrical power. Square root of P or 1200 watts in our case = 34.641 34.641/50 = 0.6928 amps. E=IIR (0.6928*0.6928)*50 = 23.99 volts. Therfor, the wire can easily handle the power. Use of a calculator helps. Your theory was correct. The decimal point was not. |
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