Explanation: A conventional AC ammeter is designed to indicate the **effective (RMS)** value of current. RMS stands for Root Mean Square, and it's the most common and practical way to quantify AC voltage and current. The significance of the RMS value is that it represents the equivalent DC current that would produce the same amount of heat or power in a resistive load. This makes RMS values crucial for calculating actual power dissipated in a circuit, which is fundamental to radio theory and circuit design. Peak values represent the instantaneous maximum current, which is higher than the RMS value and doesn't directly indicate continuous power. Average values for a symmetrical AC waveform over a full cycle are zero, making them unhelpful for general measurement. For a half-cycle, the average is less than the RMS value and doesn't reflect power equivalence. Therefore, effective (RMS) is the standard for practical AC measurements.