Lab 6: Slide-wire Potentiometer

Introduction

This tutorial guides you through the process of using a slide-wire potentiometer for measuring voltage and resistance in a lab setting. Understanding how to set up and utilize this device is crucial for accurate electrical measurements in physics experiments.

Step 1: Gather Necessary Equipment

Before starting, ensure you have the following materials ready:

• Slide-wire potentiometer
• Power supply (battery or DC source)
• Connecting wires
• Multimeter
• Resistors (for testing)
• A ruler (for precise measurements)

Step 2: Set Up the Circuit

1. Connect the Power Supply:

   • Connect the positive terminal of the power supply to one end of the slide-wire.
   • Connect the negative terminal to the other end.

2. Attach the Multimeter:

   • Set the multimeter to the appropriate voltage setting.
   • Connect one probe to the movable contact of the slide-wire potentiometer and the other probe to the ground.

3. Insert Resistors for Testing:

   • Connect a resistor in the circuit to measure the voltage drop across it.
   • Ensure all connections are secure to prevent any interruptions.

Step 3: Calibrate the Potentiometer

• Zero Setting: Adjust the slide-wire to ensure that it reads zero volts when no current flows.
• Measure the Total Length: Use the ruler to measure the total length of the slide-wire. This will be essential for calculating the voltage division.

Step 4: Conduct Measurements

1. Select a Position on the Slide-Wire:

   • Move the contact to a specific point along the wire where you want to measure the voltage.

2. Record the Voltage:

   • Read the voltage on the multimeter.
   • Note the position of the contact on the slide-wire for reference.

3. Calculate Resistance:

   • Use Ohm's Law (V = IR) to calculate the resistance if needed.
   • Rearrange the formula to find R:

     R = V/I
     

Step 5: Analyze Results

• Compare your measurements with theoretical values to identify any discrepancies.
• Use the data collected to understand voltage distribution across the potentiometer.

Conclusion

In this tutorial, you learned how to set up and use a slide-wire potentiometer effectively for electrical measurements. Key steps included gathering equipment, setting up the circuit, calibrating the device, and conducting measurements. For further exploration, consider experimenting with different resistor values or configurations to deepen your understanding of electrical principles.