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   Commercial agriculture is the type of agriculture which is concerned with the production of good, animals and cash crops in large quantities for sale. The main purpose of commercial agriculture is to gain profit from the sale of agricultural commodities.   Characteristics of commercial agriculture    •Yield is usually high.    •Commercial agriculture involves huge investment of capital.      •It employs the use of skilled labour.    •Records are kept in commercial agriculture.    •It involves the cultivation of large hectares of land.    •Irrigation system may be practised in commercial agriculture.    •It uses agro-chemicals (chemical compounds used to improve the quality and quantity of agricultural outputs) such as fertilizers, insecticides, herbicides, pesticides, etcetera.    •Only rich farmers are engaged in commercial agriculture.    •Improved v...

    A source of light is referred to as the origin of sensation in vision. A light ray is produced from one particular source. The source through which light is produced is luminous objects. It is capable of producing light rays itself.  Luminous objects : These are sources through which light rays are produced. Examples of luminous objects are : sun, star (which are referred to as self-luminous of nature), firefly or glowworms (which are referred to as self-luminous of living creature), and electric lamp, candle, torch light ,etcetera, (are referred to as man-made or artificial luminous sources).  Non-luminous objects : These are reflective surfaces which when light falls, produce rays of light. Examples of non-luminous objects are : a signboard placed by the roadside, a mirror placed in the sun, etcetera. These objects are classified into :  •Transparent objects :These are objects one can see through and light can also pass through them, ...

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...