Specific Resistivities and Ohm's Law Analysis

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Description

This lecture covers two main tasks related to specific resistivities and the analysis of Ohm's law. The tasks involve determining the length of a NiCr wire providing 65 Ohm resistance and evaluating specific resistivities using different materials like Kanthal and Cu. The instructor discusses experimental setups, calculations, and measurements for understanding the concepts of resistance and resistivities.

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The term contact resistance refers to the contribution to the total resistance of a system which can be attributed to the contacting interfaces of electrical leads and connections as opposed to the intrinsic resistance. This effect is described by the term electrical contact resistance (ECR) and arises as the result of the limited areas of true contact at an interface and the presence of resistive surface films or oxide layers. ECR may vary with time, most often decreasing, in a process known as resistance creep.

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Material is a substance or mixture of substances that constitutes an object. Materials can be pure or impure, living or non-living matter. Materials can be classified on the basis of their physical and chemical properties, or on their geological origin or biological function. Materials science is the study of materials, their properties and their applications. Raw materials can be processed in different ways to influence their properties, by purification, shaping or the introduction of other materials.

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