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radar
 one year ago
Electricity problem from Jan. 1959 issue of QST;
Using Ohm's law find.
radar
 one year ago
Electricity problem from Jan. 1959 issue of QST; Using Ohm's law find.

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radar
 one year ago
Best ResponseYou've already chosen the best response.2"There are three (3) resistors in series, but you only know three things: R1 has a value of 2 Ohms, R2 dissipates 2 Watts, and R3 has a voltage drop of 2 volts across it. Given that the power supply is a 10.5 Volt battery, how can you puzzle out the value of R2 and R3, as well as the current, I?

radar
 one year ago
Best ResponseYou've already chosen the best response.2Hint: Don't be surprised that there may be more than one solution.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[I ^{2}*R2=P2=2wats,so I=\sqrt{P2/R2}\] ,where I is current,P2 is power dissipation of R2 resistor,R2 resistane of R2 resistor,Ubattery=U3+I*R1+I*R2,where Ubattery is 10.5 U3 is 2V,R1 is 2 Ohms,and from there its quadratic journey to unknown yet still reachable positive solution of R2

radar
 one year ago
Best ResponseYou've already chosen the best response.2Yes it results in a quadratic thus the two solutions.

radar
 one year ago
Best ResponseYou've already chosen the best response.2dw:1440593442334:dwdw:1440593505020:dwMultiply all terms by I getting: \[10.5I = 2I ^{2}+2+2I\]Consolidate similar terms and place in standard form. Getting:\[2I ^{2}8.5I+2=0\]divide thru by 2 getting the quadratic in final form: \[I ^{2}4.25I+1=0\] Solve for the two real values of current and the values of R2 and R3 with each value of current.

radar
 one year ago
Best ResponseYou've already chosen the best response.2Solving the quadratic (completing the square" method Arranging the equation: \[I ^{2}4.25I = 1\]\[I ^{2}4.25I + 4.515625 = 1 + 4.515625 = 3.515625\]\[(I2.125)^{2}=3.515625\]\[I  2.125=\pm \sqrt{3.515625}\]\[I=2.125\pm 1.875\]\[I = 4\]\[I=0.25\]The conditions of current are: I=4 Amps and I can equal 250 milliamps.

radar
 one year ago
Best ResponseYou've already chosen the best response.2When I = 4 Amps Then R2 =.125 Ohm and R3 = .5 Ohm When I = .25 Amps then R2= 32 Ohms and R3 = 8 Ohms

radar
 one year ago
Best ResponseYou've already chosen the best response.2dw:1440684714597:dwdw:1440684916591:dw
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