Series–parallel circuits

Question 1

find the total resistance 𝑅ₜ of a series-parallel combination

Answer 1

1. Identify the series and parallel relationships
2. Determine total series and total parallel resistance

Question 2

find total current in a circuit

Answer 2

𝐼ₜ = 𝑉ₛ/𝑅ₜ

total current = source voltage / total resistance

Question 3

loading

Answer 3

when a load resistor 𝑅load is connected from the output of a voltage divider to ground, the output voltage is reduced by an amount that depends on the value of 𝑅load

Question 4

stiff voltage divider

Answer 4

a voltage divider in which the load resistor is at least ten times larger than the divider resistors

a stiff voltage divider has a small loading effect and are more stable, but use more power

Question 5

load current

Answer 5

in a multiple-tap loaded voltage-divider circuit, the currents through load resistors

Question 6

bleeder current

Answer 6

the current left after the total load current is subtracted from the total current in the circuit

𝐼bleeder = 𝐼total – 𝐼RL1 – 𝐼RL2 (assuming a two-tap circuit, with three resistors dividing voltage and RL1 coming off one branch and RL2 coming off the second branch)