Question

Table . Labeling Restrictors Color Codes Labeled Restrictor Value Tolerance (%) | Minimum Resistance () Resistance () Maximum Brown, red, black, gold 12 x 1 5% 11.4 12.06 68 x 1 64.6 71.4 Blue, gray, black, gold 5% Orange, white, 39 x 1 black, gold 5% 37.05 40.95 Table 2.Series Circuits 12 12 39 39 0.1084 .330 0.0522 0.647 0.0342 1.444 1.381 25.009 2.711 53.98 83.596 2.859 2.818 39 1.416 Table 3. Parallel Circuit 39 39 68 39 68 68 0.133 0.109 0.08452.83 2.78 2.81 2.83 20.9 25.75 33.49 2.78 2.78 2.81 2.83 2.81 Table 4. Currents in Parallels and in Series RI(D) Currents Series Parallel R2(D) 39 68 I, (A) 0.049 0.061 I2 (A) 0.050 0.046 39

Study the equivalent resistance readings for the series circuits.Can you come up with a rule for the equivalent resistance of a series circuit with two resistors? For each of the three series circuits, compare the experimental results with the resistance calculated using your rule. Consider tolerance of each resistor using the minimum and maximum values. Lastly, calculate the equivalent resistance of the circuit for each of the three parallel circuits.

Answer 1

Yes the rule for equivalent resistors in series is

R(eq) = R(1) + R(2)+.....

Beacuse the potential drop across 1st resistor will IR(1). The potential drop across second resistor will be IR(2) and son on. Note the current in both the resistors will be the same since they are in series.

Total potential drop should equal the potential of the battery = V

Hence V= I( R(1) + R(2)) hence equivalent resistance is R(eq)= R(1) + R(2)