Practice question · Multiple choice
Why must a voltmeter have a very high internal resistance?
Hints
- A voltmeter is wired in parallel with the component.
- Any current it draws is current the component no longer receives.
Show the answer
D. So it draws negligible current and does not lower the voltage it is reading
Why
In parallel, a low-resistance meter would divert current and reduce the very voltage being measured. High resistance keeps that perturbation negligible, the measurement problem, not a safety one.
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