Multimeter VOM

Ammeters measure current, voltmeters measure voltage,
    and ohmmeters measure resistance.

These devices are often combined into one instrument
    called a multimeter or VOM (volt-ohm-milliemmeter).

Analog versions of ammeters and voltmeters typically
    utilize a galvanometer, which relies on magnetic effect.

A needle is deflected by an amount proportional to
    the current passes through the device (coil).

A good ammeter should have a resistance that is small
    compared to other resistance in the circuit.

A good voltmeter should have a large resistance.

This java applet shows how to utilize a galvanometer into a multimeter.

The full scale current for the galvanometer is 50uA
    with internal resistance 2k ohm.

The following applet shows the simplified version
    circuit diagram for a real multimeter.

You can operate at different mode:

1. select the Mode (Voltage/Current/Resistance) :

2. select the appropriate range for that mode.

3. You can change values of the DC voltage source V and resistor R:

4. Hit the OFF/ON toggle button to connect/disconnect
    the meter to the test circuit. 5. Learn / Exercise Mode :
     Cilck the mouse at the center of the meter
        (within the white circle area)
        will toggle between exercise and learn mode,

   Learn mode: ( default )
        When the meter is connected to the test circuit,
            the needle of the meter will be shown.
   Exercise mode:
        The needle will not be shown, and you will have 3 chances
            to enter the correct value into the textField.

Thank you, Jeff Forssell, for your valuable suggestions.

Your suggestions are highly appreciated!
Please click for your feedback!

Author¡GFu-Kwun Hwang, Dept. of physics, National Taiwan Normal University
Last modified :  More physics related java applets