Knowledge batch

🗿👀🥸➡️🔤🙂😘💞💎📱📱👍🔤🔠😡አኘጀገኸቀሸነፀፀገጰፈወወወ

Biology Circulation system                _by Ibn al_Nafis 1242                _ william harvey 1628 Vaccination            _by Jenner' france 1799 Cell theory _Theodor schwann & _ matthas schleiden 1838 Germ Theory _Louis pasteur 1861 X-ray _Conrad Rontgen 1895 Vitamins _Frederick Hopkins 1900 Insulin _fredrick Banting 1920 Penicillin _Alexander fleming 1928 DNA _ friedrich miescher 1860/70 Anesthetics _Albert Niemann extracted from leaves of coca cola in 1860 _1st used in clinic by sigmund freud & karl koller HIV _Robert Gallo &luc montagnier 1980s #grade10 @knowledgebach9 @knowledgebach9

Biology Circulation system _by Ibn al_Nafis 1242 _ william harvey 1628 Vaccination _by Jenner' france 1799

Chemistry 🧪Rules for assigning Oxidation number 🌡The oxidation state of an uncombined element is zero. ✨it apply for polyatomic molecule. 🌡The oxidation number of a monatomic ion is equal to the charge on the ion. 🌡 The oxidation number of oxygen in a compound is usually -2 except 1. Peroxide is -1 2. Superoxide -1/2 3. Oxygen diflouride +2 🌡 The oxidation number of hydrogen in its entire(with non metal) compound is +1. Except in metal hydrides where its oxidation number is -1. 🌡 The sum of oxidation number of all the atoms in a neutral compound is zero. 🌡 In a polyatomic ion, the sum of the oxidation numbers of its constituent atoms equal the charge on the ion. 🌡 Elements of group IA have +1 and IIA is +2. 🌡 In a cpd , more electronegative element is assigned as negative and less electronegative is assigned as positive oxidation number. ✨Oxidation number is the number of electrons that an atom apears to have gained or lost when it is combined with other atoms. #grade10 , #Chemistry @knowledgebach9 @knowledgebach9

Physics ✨Scalar quantity...that are specified only by their magnitude. ✨Vector quantity... are quantity that are specified by their magnitude and direction. 🔸zero vector..a vector with zero magnitude and no direction 🔸 Unit vector.. magnitude equal to one 🔸Equal vector.. have same magnitude and direction 🔸negative of vector.. same magnitude and opposite direction 🔹Algebraically a vecor represented by bold letter and an arrow over the letter. 🔹Geometrically represented by an arrow where length of an arrow show the magnitude and the arrow head show the direction of vector. ✨vector addition is means of finding the resultant of a number of vectors. ✨ Subtraction of vector is addition of the negative of a vector. 👉To determine the resultant of two vector acting: ✨in the same direction add the given vector and take the common direction. ✨In opposite direction, get the difference and take the direction of the vector with the greater value. 👉 In any vector can be resolved into a horizontal and vertical component. 👉The combined effect of the horizontal and vertical components of the vector quantity is the same as the original vector.. ✨The method of finding the components of vectors is called resolving vector. @knowledgebach9 @knowledgebach9