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I think that it won’t because there is no current entering the meter with which it can measure. Correct?

Also, is it the same reason why the meter won’t show a reading even though one probe is in air and one is at a battery terminal?

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  • \$\begingroup\$ Which parts of the probes would the field assume? The field would reduce to a point at the multimeter. \$\endgroup\$
    – Chu
    Aug 30, 2019 at 14:40
  • \$\begingroup\$ @Chu Assume the probes are point-like. \$\endgroup\$
    – Atom
    Aug 30, 2019 at 14:41
  • \$\begingroup\$ It doesn’t matter what shape they are! \$\endgroup\$
    – Chu
    Aug 30, 2019 at 14:43
  • \$\begingroup\$ This is similar to: an aeroplane flies through the Earth’s magnetic field; could you measure the induced emf across the wing tips with a voltmeter? \$\endgroup\$
    – Chu
    Aug 30, 2019 at 14:47
  • \$\begingroup\$ in a strong enough field, the tiny bits of metal at the DVM connector, in the plastic cases,will gather enough displacement-current (capacitive charge movement) to indicate "a voltage" \$\endgroup\$ Sep 1, 2019 at 17:29

3 Answers 3

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If you set up a static electric field (say between two charged plates) and then place multimeter probes into it, the first thing that would happen is that the meter would read a voltage. The second thing that would happen is that the meter would discharge.

At this point, there are two interesting things to note:

  1. The meter reads zero (OK, this is only interesting in context)
  2. The electric field has assumed a different shape, because there is a structure within it (the probe wires and tips) that is all at one electric potential.
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A multi-meter can show a reading when moved through an electric field, however when its stationary, it rapidly dissipates the charge over its generally 10 megaohm input resistance, equally any charge that is developed on the probe is largely attenuated by the meters input capacitance (10's to 100's of pF)

The meter's input capacitance is also why you can measure frequencies on some meters with no ground connected. However with DC voltage the other probe quickly charges up to the DC voltage via the 10M resistance and shows 0 after the initial spike.

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Working with a buddy on piezo sensors, and experimenting with reducing the 60Hz trash floor, we found the 3' wire of a 10MegaOhm DVM would report 7 volts when hanging near the chassis of a floating unpowered computer tower.

A nearby low-quality switching-supply was coupling onto the computer tower (that measured over 50 volts by the DVM)

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