After thinking through the consolidation steps and redrawing the circuit to an equivalent resistor, the first step to solving a combination circuit is to calculate the ...

After thinking through the consolidation steps and redrawing the circuit to an equivalent resistor, the first step to solving a combination circuit is to calculate the ...

• A. component power consumed
• B. component voltage drops
• C. total current flow
• D. total resistance

Answer: (D)

Finding the total resistance is the first move after simplifying to an equivalent resistor because it tells you how much current the source will push through the entire network. Once you know R_total and you have the supply voltage, you can use Ohm’s law to get the total current. That total current then sets up the voltages across each branch and the currents in those branches, and from there you can find individual power dissipations. Without knowing the total resistance, you can’t reliably determine the total current, so the other quantities (voltage drops, branch currents, and power) can’t be determined in a consistent way.

Finding the total resistance is the first move after simplifying to an equivalent resistor because it tells you how much current the source will push through the entire network. Once you know R_total and you have the supply voltage, you can use Ohm’s law to get the total current. That total current then sets up the voltages across each branch and the currents in those branches, and from there you can find individual power dissipations. Without knowing the total resistance, you can’t reliably determine the total current, so the other quantities (voltage drops, branch currents, and power) can’t be determined in a consistent way.