(adsbygoogle = window.adsbygoogle || []).push({}); _{1. The problem statement, all variables and given/known data We connect two resistors to a battery, once with the resistor of the resistance R1 = 2 Ω, and the second time the resistor of the resistance R2 = 0.5 Ω. In both cases the resistor uses up the power of 2W. What is the internal resistance of the battery? What is the driving voltage of the battery? 2. Relevant equations P= V*I V= R*I P= R*I² P= V²/ R 3. The attempt at a solution - Now I derivate three general equations: 1) V(0)= R(1)I(1) + R(0)I(1) 2) I(1)= V(0)/ (R(1) + R(0)) 3) I(2)= V(0)/ (R(2) + R(0)) - Now I plugged these three equations in the power formula and got: P= R(1)I(1)²= R(1)*[V(0)²/ (R(1) + R(0))²] V(0)²= [P*(R(1) + R(0))²]/ R(1) P= R(2)I(2)²= R(2)*[V(0)²/ (R(2) + R(0))²] P= R(2)* [(P*(R(1) + R(0))²)/ (R(1)* (R(2) + R(0))²)] 1= [R(2)/R(1)]*[ (R(1) + R(0))²)/ (R(2) + R(0))²)] R(2)/R(1)= (R(1) + R(0))²)/ (R(2) + R(0))²) sqrt(R(2)/R(1))= (R(1) + R(0))/ (R(2) + R(0)) sqrt(R(2)/R(1))* (R(2) + R(0))= R(1) + R(0) R(0)*(sqrt(R(2)/R(1))) – 1)= R(1) – ((sqrt(R(2)/R(1)))*R(2)) R(0)= [R(1) – ((sqrt(R(2)/R(1)))*R(2))]/ [sqrt(R(2)/R(1))] R(0)= 1/3 Ω V(0)²= [P*(R(1) + R(0))²]/ R(1) V(0)²= 2.33 V Are my calculations correct? Thank you for helping!}

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# Homework Help: Circuit problem- resistance, power, voltage

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