Comment on 'Resistance of a digital voltmeter: teaching creative thinking through an inquiry-based lab'

摘要

Teaching about measurements and showing examples of instruments' nonideal behaviour are important in physics education. Digital multimeter input impedance analysis is perfect for this, since these instruments are easily available, precise enough, have good value/price ratio and represent modern technology. A recent paper (2018 Phys. Educ. 53 053005) demonstrates how the investigation of the input impedance of a digital multimeter can be used in education. However, we think that some more discussion is needed to make it more complete.