Measure an unknown resistance
The Wheatstone bridge is used to determine an unknown resistance (Rx in our case)
by adjusting a known resistance so that the measured current is zero.
To make it more fun,
you can measure voltage and current at any places in the circuit
below. Just drag the plus and minus connectors of the multimeter to any place
on the wire. The variable resistor at R2 can be changed either by dragging the green
slider or by typing a number in the text field below.
Tip: To determine the resistance put one connector each at the upper and lower
corner of the rhombus, put the meter to the most sensitive voltage setting
and determine the
resistance R2 at which there flows no current through the multimeter.
In this case the formula for Rx is given by Rx=(R1/R2)*R4.
To find more information on how and why this experiment works, look at
the background page.
Ursprunglig källa: http://dwiarda.com/scientific/Bridge.html
Översatt/anpassat SSVH Jeff Forssell
Senaste uppdatering Friday, September 29, 2000