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According to recent reports, Apple may announce its long-rumoured  satellite connectivity for the iPhone 14. The event’s name ‘Far Out’ has ticked a number of possibilities, one of which is next-level connectivity. This development was revealed after Tim Farrar, a satellite communications consultant from a California-based company, took to Twitter to share information. According to Farrar, T-Mobile and SpaceX’s announcement was most likely an attempt to delay Apple’s announcement of a satellite connectivity feature for the iPhone 14.

Watch the Throne At long last, the successor to the porcelain throne has arrived. Well, maybe. The project began in 2011, when the Bill and Melinda Gates Foundation issued the "Reinvent the Toilet Challenge." Samsung and the Gates Foundation joined up in 2019 to create the new product, which doesn't use a typical sewage system. Instead, according to a Samsung blurb about the toilet, it recycles pee through a purification process — while solid waste is dehydrated, dried, and "combusted into ashes." And they say only Apple comes up with the cool hardware! Clean Water It doesn't sound like serious stuff, but waste disposal is a significant global issue. The United Nations says that 2 billion people lack access to safe drinking water services, and 3.6 billion lack safe sanitation services. And if that's not enough, more than 700 children under the age of five die every day from diarrheal diseases because of unsafe water and sanitation conditions....

A few years ago it was impossible to charge the mobile in less than two hours, not to mention when it was necessary to fully charge the nickel batteries so that they would not suffer from the memory effect that limited their capacity. This is no longer the case and the loading times are getting shorter every day. In fact, just a few days ago the world's first mobile phone with a 200 W charge was launched, capable of fully charging its battery in 10 minutes. But, is it possible to go further? OPPO believes so, to the point that it will be possible to charge your mobile from 0 to 100% in 1 second

SpaceX is embarking on a bold new adventure: making rocket fuel out of thin air. "SpaceX is starting a program to take CO2 out of atmosphere & turn it into rocket fuel," CEO Elon Musk tweeted on Monday. "Please join if interested." Such a process — using in-situ resources to generate fuel — could have great implications during our transition to becoming interplanetary, according to Musk. "Will also be important for Mars," he added in a follow-up tweet. Carbon Appetit It's particularly a pertinent topic for SpaceX's operations, given that its workhorse Falcon 9 rocket emits plenty of CO2 when it launches. And it's not quite as far fetched as it sounds. Using a new technique called "direct air capture" (DAC), SpaceX could suck in thousands of tons of carbon dioxide to turn it into a source of fuel, Bloomberg reports. Iceland recently started operations at the world's largest DAC plant, sucking up to 4,400 tons of CO2...

Chemistry - Zinc Introduction In the periodic table, zinc is the first element of group 12. The symbol of zinc is  ‘Zn’  and the atomic number is  ‘30.’ In terms of availability, zinc is the 24 th  most abundant element found in the Earth's crust and it has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), which is a zinc sulfide mineral. Andreas Sigismund Marggraf, the German chemist, first discovered the pure metallic zinc in 1746. Interestingly, alchemists burned zinc in the air and form something different thing and they named that  "philosopher's wool"  or " white snow ." Salient Features of Zinc Zinc’s color is bluish-white and it is lustrous and diamagnetic metal. Zinc metal is normally hard and brittle; however, at when the temperature increases from 100 0 C, it becomes malleable. When temperature increases 210 0 C, then the zinc metal again becomes brittle and can be pulverized easily by beating. Zinc is a conductor of ele...

Chemistry - Platinum Introduction Platinum is a malleable, ductile, dense, and highly unreactive chemical element. The symbol of platinum is  ‘Pt’  and its atomic number is  ‘78.’ The name of platinum is derived from a Spanish term i.e. ‘platina,’ which means " little silver ." Platinum is the most precious and the rarest metal (element) on the earth. Salient Features of Platinum Following are the important features of the platinum − Platinum is a silver white metal. Platinum is an element of group 10 of the periodic table. Platinum is one of the rarest elements in the crust of the earth. Platinum is one of the least reactive elements. Platinum has six natural isotopes. Platinum is one of the most highly valuable and precious metals. Platinum is characteristically resists corrosion in all conditions. Because of this reason, it is considered as noble metal. Platinum is normally insoluble in nitric and hydrochloric acid, but dissolves in hot  aqua regia . After dissolv...

Chemistry - Silver Introduction Silver is a soft, lustrous transition, and white metal. Silver has the highest electrical and thermal conductivity; and, it has also the highest reflectivity of any metal. The symbol of silver is  ‘Ag’  and atomic number is  ’47.’ Salient Features of Silver Silver is a precious metal used since long time by human beings. Silver is an element of group 11 of the periodic table. Silver has an excellent white metallic luster commonly used in a high polish. As silver has no color; therefore, it has high reflectivity (of light). Silver has very high electrical and thermal conductivity. Its electric conductivity is the highest – higher than copper. Among all the metals, silver also has the lowest contact resistance. Occurrence of Silver The metal silver is usually found in the Earth's crust in the pure form. Silver also found as an alloy with the gold and some other metals. Silver is also found in some minerals, such as argentite and chlorargyrite...

Chemistry - Gold Introduction Gold is a bright, reddish yellow, soft, dense, malleable, and ductile metal naturally found in the earth’s crust. The symbol of gold is  ‘Au’  and atomic number is  ‘79.’ Gold is (chemically) a transition metal and belongs to group 11 of the periodic table. Salient Features of Gold Gold, which remains in a solid state under standard conditions, is the least reactive element. Gold is resistant to most of the acids. Gold does dissolve in aqua regia; aqua regia is a mixture of nitric acid and hydrochloric acid. However, gold is insoluble in nitric acid. Gold usually dissolves in alkaline solutions of cyanide. Cyanide solutions are commonly used in mining and electroplating. Gold also dissolves in mercury and forms  ‘amalgam alloys.’ Gold does not react with oxygen at any temperature. Occurrence of Gold Gold commonly occurs as a free element i.e. in the natural form. Gold occurs as nuggets or else found in in rocks, grains, in veins, and in ...

Chemistry - Copper Introduction Copper is a soft, ductile, and malleable metal. Copper has very high thermal and electrical conductivity. The symbol of copper is  ‘Cu’  and atomic number is  ’29.’ Copper is known to people since (about) c. 8000 BC. Copper is the first metal, which was smelted from its ore around c. 5000 BC. Salient Features of Copper Copper was the first metal that cast into a shape (in a mold). Copper was the first metal that successful alloyed with another metal, e.g. copper alloyed with tin and resultantly bronze is prepared. It is done about c. 3500 BC. First metal to be purposefully alloyed with another metal, tin, to create bronze, c. 3500 BC. Copper has a natural reddish-orange color; it is visible once the its surface is exposed. Copper is a very good conductor of electricity and heat. Copper is an element of group 11 of the periodic table. Copper normally does not react with water; however, it does react slowly with atmospheric oxygen and form a ...

Chemistry - Iron Introduction Iron is the most common element found in largely in outer as well inner core of the earth. The symbol of iron is  ‘Fe’  and atomic number is  ‘26.’ Iron is one of the earliest known elements that is being used by human beings. Salient Features of Iron Following are the major features of iron − Pure iron element is soft, ductile, and malleable. The boiling point of iron ranges between 1533 0 C and 2450 0 C. Iron easily gets attracted towards magnet. In dry air, iron remains inactive and does not react (with air); however, in moist air, it reacts and forms rust. Pure iron normally does not react with pure water; however, it reacts easily with ordinary of polluted water and rust forms. Iron reacts with halogen and Sulphur to form halide and sulphide accordingly. Occurrence of Iron The inner and outer cores of the earth are largely made up of iron and nickel. Most likely, iron is the most abundantly available element of the earth; however, it is ...

Chemistry - Maganese Introduction Manganese is a chemical element that usually found in combination with the iron. The symbol of manganese is  ‘Mn’  and atomic number is  ’25.’ Manganese is a metal very important for the industrial use. In 1774, Johan Gottlieb Gahn, first time isolated an impure sample of manganese metal in 1774. Features of Manganese Following are the major features and characteristics of manganese − Similar to iron, manganese is silvery-gray metal. Manganese can be oxidized easily, but very difficult to fuse it, as it is very hard and brittle. In air, manganese gets tarnished slowly (oxidization). Manganese is an element, which is part of the iron group. Occurrence of Manganese Manganese is the 12 th  most abundant element of the earth’s crust. Soil usually contains about 7–9000 ppm of manganese with an average of 440 ppm. Seawater has only about 10 ppm manganese; whereas, the atmosphere contains about 0.01 µg/m3. Pyrolusite (MnO 2 ) is the most im...

Chemistry - Magnesium Introduction Magnesium is a shiny gray solid element. The symbol of magnesium is  ‘Mg’  and atomic number is  ‘12.’ With approximately 80% of the world market share, China is the largest supplier of magnesium. Salient Features of Magnesium The density of magnesium is two-thirds the density of aluminum. Among all the alkali metals of the Earth, magnesium has lowest melting point (i.e. about 1,202 0 F) and lowest boiling point (about 1,994 0 F). Magnesium usually reacts with water at room temperature. Sometimes, magnesium is also used as an igniter for thermite. Magnesium, when burns in air, produces a brilliant-white light, which also includes strong ultraviolet wavelengths. Magnesium, when burns, it produces intense bright and white light (see image given above). Occurrence of Magnesium By mass, magnesium is the eighth-most-abundant element found in the Earth's crust. Magnesium is found usually in large deposits of magnesite, dolomite, and other such...

Chemistry - Metallurgy The branch of science and technology that studies the properties of metals and their production and purification is known as  metallurgy . Naturally occurring solid inorganic substance is known as a  mineral . Naturally occurring solid material from which valuable mineral or metal can be extracted is known as  ore . The following table illustrates the major elements and their ores − Element Ores Chemical Composition Aluminum Bauxite Al 2 O 3 2H 2 O Corundum Al 2 O 3 Kryolite Na 3 AlF 6 Dyspore Al 2 O 3 .H 2 O Copper Copper Pyrite CuFeS 2 Malachite 2CuCO 3 Cu(OH) 2 Iron Hematite Fe 2 O 3 Magnetite Fe 3 O 4 Siderite FeCO 3 Sodium Sodium Carbonate Na 2 CO 3 Sodium Chloride NaCl Sodium Nitrate NaNO 3 Sodium Sulphate Na 2 SO 4 Potassium Potassium Chloride KCl Potassium Carbonate K 2 CO 3 Potassium Nitrate KNO 3 Magnesium Magnesite MgCO 3 Dolomite CaMg(CO 3 ) 2 Epsom Salt MgSO 4 Calcium Calcium Carbonate CaCO 3 Tin Cassiterite SnO 2 Lead Galena PbS Ceruss...

Physics - Gravitation Introduction All celestial bodies those found in the universe attract each other and the force of attraction among these bodies is called as the  gravitational force . Universal Law of Gravitation Every object in the universe has the property to attract every other object with a force which is directly proportional to the product of their masses and inversely proportional to the square of the distance between them (see the image given below). F  = force of attraction between two the objects ‘A’ & ‘B’ M  = mass of ‘A’ m  = mass of ‘B’ d 2  = the square of the distance between ‘A’ & ‘B’ G  = is the constant of proportionality and is known as the universal gravitation constant. The SI unit of G is  N m 2  kg –2 . It is obtained by substituting the units of force, distance and mass (as given in the following equation − $$G = \frac{Fd^2}{M \times m}$$ Henry Cavendish had calculated the value of  ‘G’  as  6.6...

Physics - Friction Introduction Friction  is result of the irregularities on the two surfaces in contact of each other. The force of friction is dependent on the irregularities of the surface; if it is greater, then the friction will be greater and if it is smooth, then the friction will be lesser. Effectively, the friction is result of the  interlocking  of irregularities in the two surfaces. If the two surfaces (in contact) are pressed harder, then the force of friction will increase. On a frictionless surface, if an object starts moving, it would not stop ever; Without friction, it is not possible to construct a building. Friction produces heat; when a matchstick is rubbed against the rough surface, it catches fire. Substances Reducing Friction The substances that reduce friction are known as  lubricants . E.g. when oil, grease, or graphite is applied between the moving part of a machine, then it creates a thin layer; resultantly, moving surfaces do not directly r...

 Force and Pressure Introduction When an object is either pushed or a pulled is known as a force. Motion, generated in an object, is because of an action of a force. The applied force makes the table move in a given direction. The strength of a force is commonly expressed by the magnitude. Force also has direction; likewise, if the magnitude or direction changes, it directly affects the force. If the force is applied in the direction opposite to the direction of motion, then it results in a decrease in the speed of the object. If an object is in motion, then external force may change in the state or direction of motion of that object. The state of motion of an object is explained by its speed and the direction of motion. The state of  ‘rest’  of an object is considered to be the zero speed, as − An object cannot move by itself. An object cannot change its speed by itself. An object cannot change its direction by itself. An object cannot change by itself. A force may make ...

Fats Introduction Fat is a significant foodstuff for many forms of life. Fats serve structural as well as metabolic functions. The fats are molecules made up of glycerol and fatty acid. Fat is an organic compound of hydrogen, carbon, oxygen. Based on the number and bonding of the carbon atoms, fats and oils, are categorized in the aliphatic chain. fats and oil Functions of Fats Following are the major functions of Fats − Fat is a vital dietary requirement. The fat is usually the stored source of energy in the body that remained store beneath the skin. Fat acts a protective layer especially in the human body and provide protection. Some of the vitamins such as vitamin A, vitamin D, vitamin E, and vitamin K are fat-soluble, which means they can only be absorbed, digested, and transported in conjunction with the fats. Fats actively help in maintaining the healthy skin and hair. Fats insulate body organs against external shock. Fats also maintain body temperature. Fats promote healthy cell...

 Proteins proteins Introduction Proteins, which are basically biomolecules, play wide range of functions in the body of a living organism. Proteins are made up of tiny elements of different types of amino acids. A sequence of amino acid residues in a protein is known particularly by the sequence of a gene; gene is encoded in the genetic code. After formation, proteins exist for a fixed period of time and are then degraded and recycled. The proteins get recycled by the cell's machinery by the process of protein turnover. Most of the proteins contain linear polymers made up of series of up to 20 different L-α-amino acids. The amino acids in a polypeptide chain are connected by peptide bonds (see the image given below). The peptide bond, usually, has two resonance forms, which contribute some double-bond characters. Protein Structure Most of the proteins illustrate unique 3-dimensional structures (see image given below). protein enzyme combining However, proteins have not a rigid stru...