Express your answer in volts to three significant digits.
Electromotive force is a synonym for voltage. In this case, it’s 3.06 (the voltage of the battery, ignoring internal resistance).
Express your answer in ohms to four significant digits.
You know there’s a difference of 0.06 V between opening and closing the switch (3.06 – 3.00). This is due to the internal resistance of the battery. The problem also says that there’s 1.65 A of current in the circuit. Ohm’s Law gives us the formula V = IR:
V = IR
0.06 = 1.65 * Rinternal
Rinternal = 3.636 * 10-2 Ω
3.636 * 10-2 Ω
Express your answer in ohms to three significant digits.
Ohm’s law gives us the formula V = IR. Use 3.00 as the voltage (this is the voltage net of the battery’s internal resistance):
V = IR
3 = 1.65 * Rcircuit
Rcircuit = 1.82 Ω