LASER stands for Light Amplification by Stimulated Emission of Radiation. LASER is a narrow beam of light of a single wavelength (monochromatic) in which each wave is in phase (coherent) with others near it. Laser apparatus Laser apparatus is a device that produces an intense concentrated, and a highly parallel beam of coherent light. Atom … Read more
X-rays It is a form of electromagnetic radiation having a high frequency (energy) or shorter wavelength. It has no mass, no charge but has energy. It travels at the speed of light When an X-ray is projected on the human body, three things happen i.e. Pass all the way through the body deflected or scattered … Read more
For supplying a large DC load, it is desirable to use more than one generator in parallel. This arrangement provides the security that if one generator gives way, the other(s) can feed part load. Desirable Conditions for DC Generators in Parallel Same voltage rating Same percentage voltage regulation Same percentage speed regulation of the prime … Read more
Each of the following questions consists of two statements, one labelled ‘Assertion (A)’ and the other labelled the ‘Reason (R)’. Examine the two statements carefully and decide if the Assertion (A) and Reason (R) are individually true and if so whether the Reason (R) is the correct explanation of the Assertion (A). Select your answers … Read more
What is Ultrasound? Ultrasound or ultrasonography is a medical imaging technique that uses high-frequency sound waves and their echoes to create images of the inside of the body. This technique is similar to the SONAR used by submarines, echolocation used by bats, dolphins, and whales. How Ultrasound Creates an Image A gel is applied to the body area which … Read more
Thevenin’s theorem Definition In any linear bi-directional circuit having more number of elements, it can be replaced by a single equivalent circuit consisting of equivalent voltage (Thevenin equivalent voltage) in series with an equivalent resistance (Thevenin equivalent resistance). By using Thevenin’s theorem load current can be calculated either in linear or nonlinear load. Consider a … Read more
Water pollution involves contaminated water, whether from chemical, particulate, or bacterial matter that degrades the water’s quality and purity. It can occur in oceans, rivers, lakes, and underground reservoirs, and as different water sources flow together the pollution can spread. The causes of water pollution include the increased sediment from soil erosion, improper waste disposal … Read more
Sigma-delta Analog-to-Digital Converter (ADC) is used in many application including telecommunications for analog to digital conversion. A Sigma-delta ADC has a modulator and a digital filter (also called as decimation filter) as shown in Fig. 1. A modulator converts the input analog signal into digital bit streams (1s and 0s). The Sigma-delta ADC method is based … Read more
Permittivity of a Material The permittivity is the property of the material which shows the development of an electric field in the presence of an external electric field. In other words, It is the ability of the material to develop the electric field in the presence of an external electric field. It is represented by the … Read more
