In electrical experiments, which precaution addresses the offset in instrument readings?

• A. Check for a zero error
• B. Tap the meter to avoid sticking
• C. Always check polarities before closing the switch
• D. When measuring resistance use low currents/voltages to avoid heating

Answer: (A)

Zero error, an offset in instrument readings, is about ensuring the instrument reads zero when there is no signal. In electrical experiments, you address this by checking the instrument’s zero reading and adjusting it so that it shows zero with no input. Once zero error is identified, you either correct future readings by subtracting that offset or use the instrument’s zero-adjustment so measurements start from a true zero. This makes readings accurate and prevents a consistent bias from skimming through every measurement. The other precautions don’t fix offset: tapping the meter is about contact reliability, checking polarities is about direction and safety, and using low currents/voltages to avoid heating targets how resistance changes with temperature, not the baseline zero reading.