Activity 2: Wheatstone Bridge

Connect the following circuit:

• Use the power supply set to 5 V.
• For simplicity, choose $R_1$, $R_3$, and $R_x$ to have the same approximate values. Use resistance values around 5 $k\Omega$.
• Use a 10 $k\Omega$ Pot.
• With the DMM measuring DC Volts, adjust the pot. so that the bridge is balanced (there is zero volts reading on the DMM).
• Take 5 resistors between 1 $k\Omega$ and 8 $k\Omega$, and get a voltage reading, filling out the following table:
  

  Data Point	Resistance $(k\Omega)$	Voltage (mV)
  1
  2
  3
  4
  5

• Plot your data on a graph. Is it a straight line? If so, determine the slope (in mv/$k\Omega$).
• Take two "unknown" resistors, measure the voltage read by your Wheatstone Circuit, and use your graph to determine the resistance of these resistors. Check your answers against a conventional Ohmmeter.