Solving Series circuits How to Whiteboards
A Series Circuit has many voltages, but only one current 24 V 1 2 5 V1V1 A1A1 A3A3 A2A2 V2V2 V3V3 How to solve series: 1. Find the total resistance 2. Find the one current 3. Use V = IR to find voltages
A1A1 A2A2 R1R1 R2R2 R3R3 I Analogy - ping pong balls - electrons All start moving at once/speed of impulse, speed of particles Resistance anywhere along the tube limits flow everywhere
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What do the meters read? (3 SF) V1V1 V2V V 5 7 11 .870 A, 4.35 V, 15.7 V V = IR V 1 = ( 5 )(.8696 A) = 4.35 V V 2 = ( 18 )(.8696 A) = 15.7 V A1A1 A2A2
V1V1 V2V2 35 V 5 9 11 4.27 V, 17.1 V, 11.1 V R = 41 , I =.8537 A V = IR V 1 = ( 5 )(.8537 A) = 4.27 V V 2 = ( 20 )(.8537 A) = 17.1 V V 3 = ( 13 )(.8537 A) = 11.1 V 13 3 V3V3 What do the voltmeters read? (3 SF)
V1V1 V2V2 120 V 500 90 200 58.3 V, 10.5 V, 38.4 V R = 1030 , I =.1165 A V = IR V 1 = ( 500 )(.1165 A) = 58.3 V V 2 = ( 90 )(.1165 A) = 10.5 V V 3 = ( 330 )(.1165 A) = 38.4 V 130 110 V3V3 What do the voltmeters read? (3 SF)
What is the value of the mystery resistor if V 1 reads 3.17 V (3 SF) V1V1 20 V 5 7 ??? 19.5 I = V/R = (3.17 V)/(5 )=.634 A R tot = V/I = (20 V)/(.634 A) = R tot = 5 + 7 + ?? = ?? = 19.5