Title Of The Experimentelectric Circuitsstudentname ✓ Solved

Title Of The Experimentelectric Circuitsstudentname

Objectives: 1) To study the relationship between the electric current passing through a resistance and the potential difference across it. 2) Use Ohm's law to find the equivalent resistance of the different combinations of resistors. 3) To distinguish between the Ohmic resistor and the non-Ohmic resistor.

Apparatus: DC Power supply, voltmeter, ammeter, resistors, and connecting wires.

Theory and Background: The electric field inside a conductor equals zero when it is at electrostatic equilibrium, but when the charges move in a conductor, they produce an electric current, defined by the current density (J). For an Ohmic material, the ratio of the current density (J = I/A) and the electric field (E) is constant and equals the conductivity (σ). Hence Ohm's law can be written as: J = σE. For a straight wire of cross-sectional area (A = πR²; R is the radius) and length (L), a potential difference (V) maintained across it gives E = V/L.

Resistors are one of the main components of any electric circuit, and some circuits need more than one resistor to produce a high (or low) equivalent resistance. Depending on the purpose, resistors can be connected in series or in parallel.

The circuit that we will use includes specific steps for interaction via the PHET simulation tool. After connecting resistors in series and parallel, take various readings to record values in designated tables.

Paper For Above Instructions

The study of electric circuits is fundamental in understanding electrical engineering and physics. This experiment is designed to explore the relationship between electric current, resistance, and potential difference as per Ohm's law, while also distinguishing between Ohmic and non-Ohmic resistors.

1. Objectives of the Experiment

The objectives of this experiment are clear and centered around understanding the properties of resistors and how they behave in circuits. By studying these relationships, students can gain practical insight into the theoretical principles laid out in physics.

2. Theory and Background

According to Ohm's law, the current flowing through a conductor between two points is directly proportional to the voltage across the two points. The law is mathematically represented as V = IR, where V is the voltage, I is the current, and R is the resistance. This principle assumes that the material behaves in a linear way, which is typically true for Ohmic materials. Non-Ohmic materials, on the other hand, do not provide a constant resistance, exhibiting varied resistance under different conditions.

3. Apparatus and Circuit Setup

In our experiment, we utilized a DC power supply, a voltmeter for measuring voltage, an ammeter for measuring current, and various resistors, including the rheostat to adjust resistance. Before starting, the circuit must be accurately assembled as per the specified diagram in the experiment guidelines. Proper connections are crucial as they ensure accurate readings and the safety of components.

4. Procedure

The procedure begins by setting up the circuit with a single resistor and varying the rheostat to take multiple readings of current and voltage. The data collected is essential for plotting the V vs. I graphs. Moreover, swapping between resistors in both series and parallel configurations allows students to explore the effects on equivalent resistance.

5. Data Recording and Analysis

After conducting the experiments, it is essential to record your findings systematically. The first part involves computing the slope of the V vs. I graph, which corresponds to the resistance measured experimentally. For both Ohmic resistors and combinations of resistors, careful calculation and comparison of the expected versus actual results provide insight into the functionality of these components under differing circuit conditions.

6. Results and Observations

Upon plotting graphs and calculating resistances from various configurations (R1 and R2 in series and parallel), one must observe how the relationships conform or diverge from Ohm's law. Results should indicate whether the experimental data aligns with theoretical predictions, and potential discrepancies should be addressed.

7. Conclusion

The experiment concludes with a comprehensive assessment of Ohmic vs. non-Ohmic resistors. The findings affirm that Ohmic materials maintain constant resistance with varying voltage and current, while non-Ohmic materials present a variable resistance. This practical understanding is crucial for future electrical applications, circuit construction, and the continued study of electrical phenomena.

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