Discussion:Ohm's Law describes the relationship between the resistance (R) of a wire, the voltage drop across it (V), and currentthrough it (1):V = RI(1)Applying a known current to a wire and measuring the voltage across it will let you determine the resistance of thewire by solving equation 1:(2)The resistance of a particular element depends on its geometry, the resistivity and the temperature. Resistivity is thetendency of the material to behave as a resistor and is an inherent property of a material, in the same sense that density orthermal expansion are inherent properties. Materials with lower resistivity, like copper, are good conductors of electricityand widely used in cireuit components while those with larger resistivity, like rubber, are used as insulators.For a wire with length (L), cross-sectional area (A), and made from a material with resistivrity (p) the resistance (R)will be given by the following equation:R= ,L(3)In case that the geometry (length and cross sectional area) and the resistance of the wire is known, then is possible tocaleulate the resistivity solving equation 3:RA(4)A wire can be consider as a long cylinder; then the cross sectional area would have a circular shape as shown inFigure 2..Cross SectionalAreaLengthFigure 2Then the cross sectional area of the wire can be caleulated using the equation of the area of a cirele:A = mr?(5)In this experiment, you will measure V and I to determine R for various lengths of wire. You will then make a graphof Resistance (Y-axis) versus length (X-axis). The plot will result in a straight line that has a slope equal toslope =,(6)From equation 6, it is possible to solre the resistivity in terms of the slope and the cross sectional area:p = slope + A(7)The manufacture values of the resistivrity corresponding to the wires used in the experiment are reported in Table 1.These values will be used as the theoretical when caleulating percent error.Table 1. Theoretical resistivity of different materials according to manufacturer.| Attractedto Magnet Dinmeter (m)NoMaterialColorResistivity (Qm)7.0 x10*BrassYellow0.0005080.0008130.0010160.001270CopperNicbromeNoDark Gray NoDark Gray1.8 x10*105 x1079 x10Red0.0010160.001016StainlessYes0.001016Steel Table 3 - Resistivity of Different MaterialsLength of the wires: 0.240 mCross SectionalCalculateTheoreticalDiameterResistanceVoltage(V)СuтеntPercentAreaResistivityResistivity(m)(A)( )( )( )Error0.0010160.005751.097750.0010160.29340.961210.0010160.22000.95525

Table 3 - Resistivity of Different Materials Length of the wires: 0. 240 m Cross Sectional Caleulate Theoretical Diameter Voltage Current Resistance Percent Area Resistivity Resistivity (m) (V) (A) Error ( ) 0.001016 0.00575 1.09775 0.001016 0.2934 0.96121 0.001016 0.2200 0.95525

Table 3 - Resistivity of Different Materials Length of the wires: 0. 240 m Cross Sectional Caleulate Theoretical Diameter Voltage Current Resistance Percent Area Resistivity Resistivity (m) (V) (A) Error ( ) 0.001016 0.00575 1.09775 0.001016 0.2934 0.96121 0.001016 0.2200 0.95525

Physics for Scientists and Engineers, Technology Update (No access codes included)

9th Edition

ISBN:9781305116399

Author:Raymond A. Serway, John W. Jewett

Publisher:Raymond A. Serway, John W. Jewett

Chapter27: Current And Resistance

Section: Chapter Questions

Problem 27.76AP

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Similar questions

Resistors are commonly rated at 18W,14W,12W ,1 W and 2 W for use in electrical circuits. If a current of1 = 2.00 A is accidentally passed through a R=1.00 resistor rated at 1 W, what would be the most probable outcome? Is there anything that can be done to prevent such an accident?
Use the atomic theory of matter to explain why the resistance of a material should increase as its temperature increases.
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When the current in the portion of the circuit shown in Figure P32.65 is 2.00 A anti increases at a rate of 0.500 A/s, the measured voltage is Vab = 9.00 V. When the current is 2.00 A and decreases at the rate of 0.500 A/s. the measured voltage is Vab = 5.00 V. Calculate the values of (a) I. and (b) R
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