The property of a material that opposes the flow of current through it, is called electrical resistance or simply resistance. The symbol of resistance is shown in the fig. 1. Practically, the electrical components that offers certain opposition (resistance) to the flow of current in the circuit is known as resistor. Fig. 1(b) shows some … Read more
In electrical circuits, the classification of circuit elements can be classified as Linear and non-linear element Active and Passive element Unilateral and Bilateral element Time-variant and Time invariant element Linear and non-linear element An element or a system is said to be linear if it obeys the principles of additive and homogeneity properties. For linear elements, … Read more
Functional Block diagram of Digital Frequency Meter Working principle of Digital frequency meter 1. The unknown frequency signal is fed to the Schmitt trigger. The signal may be amplified before being applied to Schmitt trigger. 2. In a Schmitt trigger, the signal is converted into a square wave with very fast rise and fall times, then … Read more
Difference between the construction of PMMC and dynamometer instruments PMMC (Permanent moving magnet coil) Instrument (1) Moving Coil: The moving coil is wound with many turns of enamelled or silk-covered copper wire. The coil is mounted on a rectangular aluminium former which is pivoted on jewelled bearings. The coils move freely in the field of … Read more
Recombination and trapping processes in a semiconductor Recombination is the process where an electron moves from the conduction band into the valence band so that a mobile electron-hole pair disappear. Classical mechanics requires that momentum be conserved in an encounter of two particles. Since the momentum is zero after recombination, this conservation law requires that … Read more
Magnetic bubble memory consists of magnetic bubbles used to store data bits. These bubbles move in thin films of magnetic material. The bubbles are cylindrical magnetic domains having polarization opposite to that of the thin film in which they are embedded. A thin film of magnetic garnet contains wavy strips of magnetic domains when an … Read more
Fuse was patented by Thomas Edison in 1890. Fuse is the simplest & cheapest device used for interrupting an electrical circuit under short circuit or excessive. The fuse element is generally made of materials having low melting point, high conductivity and least deterioration due to oxidation e.g., silver, copper etc. Definition of fuse It is … Read more
In this article, we will learn about Squirrel cage and slip ring induction motors. These motors are having the difference in rotor construction. Squirrel cage Induction Motor In Squirrel cage induction motors the rotor is simplest and most rugged in construction. Cylindrical laminated core rotor with heavy bars of copper or Aluminum is used for conductors. … Read more
Flags Flags are flip-flops that store bit 0 or 1 based on the arithmetic or logical operation performed by an arithmetic and logical unit (ALU). In most of the operations, the result is stored in the accumulator. There are five flags present in 8085 microprocessor. All the flags are present in an 8-bit register called as status … Read more
The phototransistor is a semiconductor light sensor formed from a basic transistor with a transparent cover that provides much better sensitivity than a photodiode. It is basically a 3-layer semiconductor device which has a light-sensitive base region. The base senses the light and converts it into the current which flows between the collector and the … Read more