Page 1of 3Ohm’s LawIntroductionIn this lab you will study the concepts of electric resistance and resistivity.Special equipment notes1. Note the tips on wiring and meters attached at the end of this lab. This is the same appendix that was attached to the Oscilloscope lab. 2. The DC power supply includes a current-limit safety feature. You cannot exceed a set value; a front-panel light will come on if you do. Avoid this. Also, since this is a “constant voltage” supply, you should find voltage readings to be quite steady, while current readings may vary with contact resistance, etc. TheoryOhm’s Law states that the voltage drop V (volts - V) across a resistor R (ohms - Ω) is proportional to the current flow I (amperes - A), namely (1) A sample that follows this equation is said to be “ohmic”. The resistance of a cylindrical conductor is (2) where L and A are the length and cross-sectional area of the conductor respectively, and ρis the resistivityof the conducting material. Resistivity is a material property (like density), which is independent of size or shape. ProcedurePart 1: (I, V) for a carbon resistor 1. Find the nominal value of R, based on the color code. 2. Measure R using the ohms range of the Digital Multimeter (DMM). The resistor must be out of the circuit!