Skssknowledge

-: ATOM MODEL Man had always been curious to know the details of the constituent of matter. Structure of atom, which is the smallest particle of matter which takes part in a chemical reaction, has always been one of the main targets of scientists.         An explanation regarding the structure of atom is called an atom model . -: THOMSON'S ATOM MODEL J. J.  Thomson gave the first idea regarding structure of atom. The model is known after him as Thomson's atom model . According to this atom model whole of the positive charge is distributed uniformly in the form of a sphere. Negatively charged electrons are arranged with in this sphere here .👇👇 The model is popularly known as plum-pudding model . Every electron is attracted towards the centre of uniformly charged sphere while they exert a force of repulsion upon each other. -: RUTHERFORD'S EXPERIMENT Rutherford performed experiments on the scattering of alpha* particles by extremely thin metal foils.   ...

Herbarium Herbaria Play an important role in taxonomy. They give important information regarding plant species for classification of plants. These are source of taxonomic research. IMPORTANT HERBARIA AND BOTANICAL GARDENS OF THE WORLD Important Herbaria :                 The art of Herbarium was started by an Indian taxonomist Luca Ghini(1490-1556). The concept of preserving plant specimen in dired from is 450 years old. The oldest preserved herbarium specimen is kept in Rome, collected by the naturalist Gherardo Cibo. From long past different countries all over world started collecting harbaria. 1. Maseum National d' Historica naturelle, Paris - 10,500,000 2. Royal Botanic Garden, Kew - >5,000,000 3. Komavov Botanical Institute, Leningrad - >5,000,000 4. Conservatoire et Jardin Botaniques, Geneva - 5,000,000 5. New York Botanical Garden, New York - 4,300,000 6. Harvard University, Cambridge, USA - 4,250,000 7. U.S. National Herbarium, Washi...

-: Introduction Before going to study ecology, We should know about life and environment. Life originated in our earth around four billion years ago. It is generally agreed that all life forms of today evolved by a common descent from a single primitive life form. It is not known how this early life form came into existence, but scientists think that it was a natural process which took place perhaps 3,900 million years ago. They were found in iron and silica rich rocks which were once hydrothermal vents in the Nuvvuagittuq greenstone belt of Quebec, Canada. If this is the oldest record of life on earth, it suggests ' an almost instaneous emergence of life ' after oceans were formed 4.4 billion years ago. Moreover a scientific study showed that geological formation of stromatolites of 3.45 billion years old contain fossilized cyanobacteria and stromatolites were also the oldest known life records on earth. -: CONCEPT OF ECOLOGY After knowing about life, living organisms, biosphe...

What is Coronavirus ? Coronavirus or who is called SARS-COV-2 . And we are also known as that the disease is cause by coronavirus is called as coronavirus disease OR COVID-19. It actually started in the first week of December 2019. And the place where coronavirus was first reported, that is south China (wuhan) sea food market. here  👇 👇                  All kinds of meat and animal products were sent to this market, like dog meat, pig, snake, bats, etc. All in one place. And south China wuhan sea food market is considered to be the starting point of this Coronavirus out breaking. The thing is that the coronavirus was earlier found in animals, And this is generally virus found in animals. And the market where animal products are kept together like this, so this gave the situation virus a chance that it could come from animals to humans.  And exactly this happened in the first week of December in 2019. A question must have come...

Hellofriends,   Anti-virus for your mind by sandeep maheshwari Sir. That video is most helpful for everyone by sandeep maheshwari Sir, is given below. Sandeep maheshwari sir's best tips for everyone on the critical situation now, to take right decision in this time. And I am also talk about our ideal Sandeep maheshwari Sir,  Sandeep maheshwari Sir is a name among millions who struggled, failed and surged ahead in search of success, happiness and contentment. Just like any middle class guy, he too had a bunch of unclear dreams and a blurred vision of goals of his life . All he had was an undying learning attitude to told on to. Rowing through ups and downs, it was time that taught him the true meaning of life. So i have provided the Anti-virus of your mind video below, and request to everyone take right decision after see the video 👇 👇  And please share it with everyone to help them to fight against coronavirus. And see the video till end please.  Thanks all.  ...

Optics -: What is optics? And It has mainly 3 contents that is - -》 Contents -: 1. Reflection of light 2. Refraction and deviation produced by prism 3. . Wave optics (link) Who want to study about 3rd content like 'Wave optics' after know about 1st content (reflection of light). Click here 👇👇 So we are derived the 1st content of Optics -: 1. Reflection of light -    -:  LIGHT It is an agent which produces in us the sensation of sight. It is a form of energy. No doubt this definition of light holds good only for a small portion of light, we shall be mainly concerned with light having this property. Various theories regarding the nature of light shall be discussedat appropriate places in this article. Some terms connected with light.  Some of the following terms shall be more oftenly used during study of Optics. 1. Source.  A body which emits light in all directions is said to be the source of light. The source may be a point one or an extended one. A source is ...

Introduction  Communication of messagefrom one place to another has alwaysbeen an important feature of our everyday life. Earlier, communication was done by beating of drums, by smoke signals or through pigeons. With the development of science, a necessity was felt for faster communications. Now we are relying on communication through electrical waves, which travel with velocity of light  ( 3× 10^8 ms^-1) .     The basic idea is to convert our primary information into electrical waveform (signals) which propagates through a channel. As the signal propagates, it becomes weaker due to resistance and some noise also creep in.  The speed of communication depends upon the number of signals transmitted in one second i.e. the frequency of signals. If we want to increase the speed of communication, we shall have to compress the waveform in a certain time so that greater number of signals are transmitted in one second. This necessitates a greater band-width of the channe...