1. OBJECTIVE
This experiment explores Ohm's Law and its implications for electrical circuits. Initially, you will investigate the concept of electrical resistivity and find the relationship between resistivity and electrical resistance. In a second phase, you will investigate how current and voltage are related through Ohm's Law.


At the end of this experiment, you should be able to:

characterize the resistance of a solid cylindrical conductor as a function of resistivity, diameter and length.

relate the magnitudes of resistance, current and voltage through Ohm's law.

use a multimeter to measure electrical resistance;

construct and analyze the characteristic plot of electrical resistance R versus length L of a wire ohmic resistor.

2. WHERE TO USE THESE CONCEPTS?
Ohm's law governs the behavior of resistive electrical circuits and has application in the most varied fields that use these circuits to drive or control systems or equipment. Among the many applications of this law, one can cite its use for the specification of electrical equipment, design of electrical protection systems and dimensioning of electrical cables in residential and industrial installations, among others.


3. THE EXPERIMENT
In this experiment you will use the Dias Blanco panel to study Ohm's law. Initially, you will investigate how electrical resistance varies in different wires with different gauges and materials. In this first phase, you will correlate electrical resistance with electrical resistivity, length and diameter of conducting wires. In a second step, you will explore the relationship between resistance, current and voltage in conducting wires.


4. SECURITY
The experiment was designed not to bring physical risks, so you will use light and harmless objects, but even with these precautions thought out and defined, the use of personal protective equipment is extremely important to guarantee safety during experiments. . In this experiment, the use of a lab coat is recommended.


5. SCENARIO
You will find on the workbench: The Dias Blanco panel with resistors, a multimeter with test leads and a voltage source with a switch.



Panel Dias Blanco: Composed of terminals to position the test leads and resistor wires made of different materials and diameters.

Multimeter: It is used to obtain measurements related to the electrical circuit, such as current and voltage.

Voltage source: Base where the dynamometer is hung so that the cylinder is immersed in the beaker with distilled water.

Test leads: They are used to connect the multimeter to the different measurement points.

Switch: Used to turn circuits on and off.