| 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. |