Final answer:
Calculating equivalent resistance, current, and voltage drop in a circuit involves reducing the circuit step by step, using Ohm's law, and knowing the fundamental relationships between current, voltage, resistance, and power.
Step-by-step explanation:
Equivalent Resistance, Voltage Drop, and Current in Circuits
Calculating the equivalent resistance of a combination circuit that includes resistors in both series and parallel configurations involves reducing the circuit step by step. First, combine resistors in series by simply adding their resistances. Then, for parallel resistors, use the formula 1/Req = 1/R1 + 1/R2 + ... + 1/Rn, where Req is the equivalent resistance, and R1, R2, ..., Rn are the individual resistances of the resistors in parallel.
Once the total equivalent resistance is determined, use Ohm's law, V = IR, to calculate the current flowing from the battery through the circuit. Then you can calculate the voltage drop across each resistor again using Ohm's law. The power dissipated by each resistor is then calculated using P = I2R, and the total power supplied by the battery is P = Iε, where I is the current and ε is the electromotive force (voltage) of the battery.
Note: Do not forget to take into account the direction of current flow and the polarity of the voltage when applying these calculations to a real circuit.
To measure the voltage and current in the circuit, connect a voltmeter across each resistor to measure voltage drop and an ammeter in series to measure current. It is important to always observe proper safety protocols when working with electrical circuits.