Science > Physics > Circular Motion > Angular Displacement, Velocity, and Acceleration Angular Displacement: For a particle performing a circular motion the angle, traced by the radius vector at the centre of the circular path in a given time is called the angular displacement of the particle at that time. It is denoted by ‘θ’. Its […]
Science > Physics > Circular Motion > Introduction Concept of Circular Motion: The motion of a particle along the circumference of a circle is called circular motion. It is a translational motion along a curved path. Examples: The motion of the earth around the sun. The motion of a satellite around the planet. The motion of […]
Science > Chemistry > Everyday Chemistry > Mechanism of Action of Drug In this article, we shall study the meaning of the term drug, and the mechanism of actions of drugs. Drugs: The word dug is derived from a French word drogue which means a dry herb. Drugs are chemicals of low molecular mass which […]
Science > Physics > Communication > The Internet and Other Technologies The Internet: According to Webopedia, the Internet is a worldwide system of connected networks. Each network consists of millions of computers, servers, routers, and printers. The Internet is also called the Information Super Highway. The data move across the networks because all the service providers use […]
Science > Physics > Communication > Amplitude Modulation The first amplitude modulated signal was transmitted in 1901 by a Canadian engineer named Reginald Fessenden. He used a continuous spark transmission and placed a carbon microphone in the antenna lead. This transmission was very crude, signals were audible over a distance of a few hundred metres. The […]
Science > Physics > Communication > Modulation Before the concept of the modulation, the signal used to be sent in form continuous wave with periodic interruption as in morse code. To code, send and decode such message high expertise was required. The direct current is not suitable for transmitting the data because of its steady nature. […]
Science > Physics > Communication > Optical Fibre: Principle and Working The optical fibre is a device which works on the principle of total internal reflection by which light signals can be transmitted from one place to another with a negligible loss of energy. Characteristics of Optical Fibre: It has a large bandwidth. The optical […]
Science > Physics > Communication > Communication Channel: Line Line Communication: Space communication is unguided communication. In this communication channel, there is no physical contact between the transmitting and the receiving antenna. The transmitted signal spreads in all directions. This results in the attenuation of the signal. To avoid the attenuation we use line communication. […]
Science > Physics > Communication > Satellite Communication Radio Communication uses ground wave, skywave, and space wave propagation. Ground wave and space wave communication are restricted to small distances, whereas skywave propagation uses frequencies ranging from 3 MHz to 30 MHz. Very high frequency (> 30 MHz) and microwave communication over long distances use a Satellite. […]
Science > Physics > Communication > Coverage Area of Antenna An antenna or aerial is a system of elevated conductors which couples the transmitter or receiver to the communication channel. Thus it is required at both ends i.e. transmitter end and receiver end. The same antenna can be used for transmitting and receiving functions. Expression […]