According to the correct method for measuring resistance, what is wrong when the meter is connected across Resistor 1?

When a measurement is taken across Resistor 1 in a circuit that includes another resistor (Resistor 2), the meter measures the equivalent resistance of both resistors rather than just Resistor 1. This occurs because the meter is connected across Resistor 1, and if Resistor 2 is also part of the circuit path, the resistance from both components is included in the measurement.

This situation can lead to an inaccurate reading when trying to determine the resistance of Resistor 1 alone, as the presence of Resistor 2 skews the results. To accurately measure the resistance of a single component, it is typically necessary to isolate that component from the rest of the circuit. By ensuring only Resistor 1 is connected to the meter, the reading would reflect its true resistance without interference from any other resistors in the circuit.

Other options present alternative scenarios that either affirm the correctness of the setup or address different aspects of resistance measurement, but they do not accurately describe the impact of measuring across multiple resistors in series or parallel.