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What Is Subsistence Agriculture ?             As men progressed from the hunting and gathering stage, they developed the art of cultivating certain plants and domesticating certain animals. People became self-sufficient and began to group themselves in villages. They made crude implements and learned to provide enough food for the family. They adopted the method of shifting cultivation and mixed farming. This practice can still be found today in very isolated areas where communication has been limited, and the people have not been exposed to modern farming techniques. It is also found where surplus capital for investment is not available. This practice is known as "subsistence agriculture".              First of all, what is "subsistence" and what is "agriculture" ?. Subsistence means the state of having just enough money or food to stay alive. For the meaning of agriculture click  here . Therefore ...

                  What is agriculture ?           The term "agriculture" is derived from two Latin words : ager, meaning field, and cultura, meaning cultivation. Literally, agriculture means field cultivation.             Today, however, the term is usually more broadly defined as the production of plants and animals which are useful to man. It covers not only the cultivation of the soil and the feeding and management of crops and livestock, but also the preparation of plants and animals  products for use by man, and the disposal of these products by marketing, because production is not complete until it gets to the final consumer.               Scope of agriculture       The main branches of agriculture include the following :  (1). Animal Science : This is the science involved in the production of animals(animal h...

      I assume that we all know  what matter is (anything that occupies space and has mass). Matter is being classified in two ways, physically and chemically. Matter is classified physically into its state (solid, liquid   and gas), but in this post we are  going to focus on the chemical classification of matter. Matter is classified chemically into : elements, compounds and mixtures. Let's start with elements.            What Is An  Element ? An element is a substance which cannot be broken down (decompose) into simpler units by chemical reactions. The elements that are recognized are 118 in number, 90 of these elements occur naturally, while the rest are artificially made. Most of the earth's crust is made up of a relatively small number of elements.  Symbols are used to represent elements as they make it easier for us to write them down and remember them. Elements are arranged according ...

       Lenz's law states that the induced current flows in such a direction as to oppose the motion producing it. This is often called Faraday's second law of electromagnetic induction. The law gives the direction of the induced emf when the current in the primary coil is increased.          The direction of the induced current in the secondary coil will be in the opposite direction.  The direction of the induced current in such that it tries to oppose the movement of the magnet towards the solenoid.         The factors on which the magnitude of the induced emf depends on the following: 1.The strength of the magnet (magnetic flux or lines of force linking the circuit.) 2.Number of turns in the coil (solenoid) 3.The distance between the magnet and the coil. 4.The surface area of the coil. 5.The relative speed between the magnet and the coil.        When a metallic sheet, ei...

            An oxidizing agent is a substance that is reduced in a chemical reaction ,thereby bringing about oxidation, while a reducing agent is oxidized thereby, bringing about reduction. E. g.   CuO + CO  --}  Cu + CO2 In the equation above :     1.CuO loses oxygen to CO to become , and it is therefore reduced. 2.CO gains O to become CO2, and therefore it is oxidized.    3.The CuO is reduced by the CO and thus CO is the reducing agent. 4.The CO is oxidized by the CuO and thus CuO is the oxidizing agent.           An oxidizing agent is a substance that accepts electrons, while a reducing agent is one that donates electrons. An oxidizing agent is also a substance in which the oxidation number decreases in the positive direction, while reducing agent is one in which the oxidation number increases in the positive direction. A substance can act as both oxidizing and reducing a...

         You may have heard of chemical reactions and equations, you may also be a novice to it, but sit tight and learn about how to balance chemical equations using the simplest method chemical equations. Balancing chemical equations might be a big deal for you, if you don't know how to go about it. In this post, I would be sharing my knowledge on balancing Chemical equations.         What are chemical equations ?? Chemical equations are just like writing a narrative essay, just to shorten or abbreviate a composition of chemical reactions in terms of the symbol and formula of the elements and compounds involved in the chemical reaction. The elements and compounds that engage in the chemical reaction which are called "the reactants" are written on the left - hand side of the chemical equation, while the products of the chemical reaction are written on the right - hand side of the chemical equation. The reactants and produc...