In communication using radio waves, an antenna at the transmitter radiates of Electromagnetic waves (em waves), which travel through the space and reach the receiving antenna at the other end. As the em wave travels away from the transmitter, the other end. As the em wave travels away f…
"Communication is the act of transmission of information". Every living creature in the world experiences the need to impart or recive information almost continuously with others in the surrounding world. For communication to be successful, it is essential that the sender and th…
The Zorth Low of Thermodynamics led us to the concept of temperature that agree with our commonsense notion. Temperature is a maker of the 'hotness' of a body It determine the direction of flow of heat when two bodies are placed in thermal contact. Heat flow from the body at a hig…
In our daily life we come across various kinds of motions. You have already learnt about some of the e.g. rectilinear motion and motion of a projectile. Both these motions are non- repetitive. We have also about unform circular motion and orbital motion of planets in the solar system. I…
Convection is a mode of heat transfer by actual motion of a matter. It is possible only in fluids. Convection can be natural or forced. In natural convection, gravity plays an important part. When a fuild is heated from below, the hot part expands and, therefore, becames less dense. Bec…
In this article we shall study laws that govern thermal energy. We shall study the processes where work is converted into heat and vice versa. In winter, when we rub our palms together, we feel warmer; here work done in rubbing our palms together, we feel warmer; here work done in rubbing…
Introduction We all have common- sense notions of heat and temperature. Temperature is a measure of 'hotness' of a body. A kettle with boiling water is hotter than a box containing ice. In physics, we need to define the notion of heat, temperature etc., more carefully. In this art…
In the article, we studies the motion of objects oscillating in isolation. What happens in a system, which is a collection of such objects? A meterial medium provides such as example. Here, elastic forces bind the consituents to each other and, therefore, the motion of one affects …
A major of all living organisms is made up of water. Human body has about 65% and some plants have as much as 95% water. It is a crucial compounds for the survival of all life forms. It is a solvent of great importance. The distribution of water over the earth's surface is not uniform…
'' Hydrogen, the most abundant element in the universe and third most abundant on the surface of the globe, is being visualised as the major furture source of energy''. Hydrogen has the simplest atomic structure among all the elements around us in Nature. In atomic form it…
Dry Cleaning of Clothes Tetra chiroroethene wase earlier used as solvent for dry cleaning. The compound contaiminates the ground water and is also a suspected carinogen. The process using this compound is now being replaced by a process, were liquefied carbondioxide, with a suitable de…
Introduction It is well known fact that self- sufficiency in food has been achieved in India since late 20th century by using fertilizers and pesticides and exploring improved methods of farming, good quality seeds, irrigation etc. But over exploitation of soil and excessive use of fertil…
About 75% of the solar energy reaching the earth is absorbed by the earth's surface, which increases its temperature. The rest of the heat radiates back to the atmosphere. Some of the heat is trapped by gases such as carbon dioxide, methane, oxone, chloroflorocarban compounds (CFCs…
Dihydrogen releases large quantities of heat on combustion. The date on energy reased by combustion. The data on energy released by combustion of fuels like dihydrogen, methane, LPG etc., are compared in terms of the same amounts in mole, mass and volume. From this table it is clear tha…
Pathogenesis: The most serious water pollutants are the diseases causing agents called pathogens. Pathogens include bacteria and other organisms that enter water from domestic sewage and animal excretra. Human excretra contain bacteria such as Escherichia coli and Streptococcus faecolis…
Domestic wastes are collected in small bins, which are then transferred to community bins by private or municipal worker. From these community bins , these are collected and carried to tht disposable site. At the site, garbage is sorted out and separated into biodegradable and non- biodeg…
