Re: Measuring mA (debate solution needed)



James Lerch wrote:

So,

A friend and I are having a polite debate.

He's calculating the current in a circuit my measuring the voltage
drop across a 20ohm resistor. (Current is ~30mA range for refernce)

I think best approach is to put a mA meter in series with circuit and
read the meter. He disagrees and said his method of measuring the
voltage drop across the resistor is more accurate.

You mean a moving coil meter ? They are inherently inaccurate (subject to modest
calibration, linearity and measurement errors due to parallax).

Graham

.

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