Basic Concepts: Resistance, Capacitance and Inductance

     In this second post of the blog, I'll be introducing some basic concepts about electronics that are a necessary and important. I'll be telling basics about  resistances, capacitance and inductance.

     Starting with resistance, it is the property of a material to oppose the flow of electric current through it. Resistance offered differs from one substance to another. The substance which offer lower resistance is called a conductor, for e.g., metals. The substance which has high resistance is called an insulator, for e.g., non metals, rubber, glass,etc. The unit for measuring resistance is ohm and

symbolized as Ω. A conductor is said to have resistance of one ohm if a potential difference of 1 volt is applied and current of 1 ampere passes through it.

     The resistance of conductor is directly proportional to its length, inversely proportional to area of its cross section, nature of material and temperature of the conductor itself. The electronic component used in circuits to provide resistance is called a Resistor.

      Moving on to inductance, it is a property of conducting coil that opposes any change in current flowing through it. This property can be understand easily with help of Lenz's Law which says "If an induced current flows, its direction is always such that it will oppose the change which produced it."

Inductance can be defined as ratio of flux linkage to the current flowing through coil. Unit of inductance is henry and symbolized as H. The component used in circuit is called an Inductor.

     The inductance of an inductor is directly proportional to square of number of turns and area of cross section, it is inversely proportional to length and depends on absolute permeability of magnetic material.

     

     Finally capacitance, it is the property of the electronic component capacitor to store the charge when its plates are at different potentials. If Q coulombs of charge is applied to one of the plates of a capacitor and potential difference of V volt is applied between the two plates its capacitance is given by  C=Q/V. The unit of capacitance is farad, with f as symbolic representation.

     Capacitance of the capacitor is directly proportional to area of plates, inversely proportional to distance between two plates and depends on absolute permeability of the medium between the plates. The medium use is generally a dielectric substance.

   The next post will be most probably about basic components that we use, symbols, and much more interesting...