Dr Rajiv Desai
An Educational Blog
THE ENERGY
THE ENERGY Energy is defined as a capacity/ability to do the work and it is measured in Joules. Power is defined as the rate at which the work is done which means work divided by time and it is measured in Watts. 1 watt= 1 joule per second. 1 Giga-joule(GJ)= 1 billion joules 1 Exa-joule(EJ)= 1 billion GJ. 31.7 watts= 1 GJ per year. 1 kilo-calorie= 4.2 kilo-joules. 1 kilo calorie is the amount of energy required to raise the temperature of 1 kg of water by 1 degree celsius. Calorie is the unit of energy in nutrition. Human being needs 2000 kilo calories of energy through food for all activities per day which is equivalent to 90 watt light bulb. Energy makes change and does things for us.Energy lights homes, cooks food,runs car/fan/AC/heater/machines/TV etc.We will go back to stone age if there is no energy. First industrial revolution was […]
THE WATER
THE WATER : Water is defined as a ubiquitous chemical substance having 2 hydrogen and 1 oxygen atoms bonded to form a molecule H2O, also known as hydrogen oxide.Deuterium is an isotope of hydrogen which combines with oxygen to form heavy water(D2O). Water is essential for survival of life as well as essential for economy,industry,ecology,climate cycle and agriculture. 60 % of human body and 80 % of human brain is water.Adult human needs 2 to 3 liters of water daily for drinking and a human can not survive for more than few days without drinking water.75 % of all people in the world are chronically dehydrated leading to day-time fatigue,cancer risk,poor mental ability and body pains.Minimum water requirement per person per day is 50 liters for drinking,bathing,cooking and sanitation.America/Canada uses 2 to 8 times more water per person than most developing nations.Civilisations have developed around water sources/rivers. Water refers to […]
THE COMPUTER AND INTERNET
THE COMPUTER AND THE INTERNET: Prologue: Millions of people read my comments on internet and yet,majority of them have very little knowledge of computer/internet and hence I am posting this comments to educate them. Today,we live in computer age,the computers are found everywhere and it has created global awareness. Computer is defined as a programmable machine that computes(stores,processes and retrieves) information(data)according to a set of instructions(program). Church-Tuning theory of mathematical versatility suggests that any computer with certain minimum capacity,in principle, can perform the same task that any other computer can perform. Computers are of 2 kinds,analog and digital. Analog computer is slower,having continuous inputs and uses mechanical devices like gear/rachet/lever to perform mathematical task, for example,speedometer in a car or electricity meter in house etc.It translates variables in a given problem into analogous variations in electrical quantity like current/voltage and solve original problem by solving an equivalent problem(analog) in electrical […]
