COMMUNICATION 1800 Telegraph defined from the Greek... TELE = Afar GRAPHOS = Write 1809 First telegraph in Bavaria. Samuel Soemmering. Used 35 wires with gold electrodes in water. Detection at distant end 2000 feet away was by the amount of gas caused by electrolysis. 1828 First telegraph in the USA. Harrison Dyar sent electrical sparks through chemically treated paper tape to burn dots and dashes. 1840 Samuel F.B. Morse and Alfred Vail were issued a patent for the first practical telegraph based on electromagnets
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IGCSE Complete Chemistry Notes Unit 1: States of matter Everything is made of particles. Particles in solid are not free to move around. Liquids and gases can. As particles move they collide with each other and bounce off in all directions. This is called random motion. In 2 substances‚ when mixed‚ particles bounce off in all directions when they collide. This mixing process is called diffusion. It’s also the movement of particles without a force. The smallest particle
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Submitted to: Submitted by: Er. R.K. Sharma Sourabh Bansal HOD (EEE) 6080709649 EEE 7th Sem. Contents Acknowledgement 1. Water powered vehicle • Introduction • Working • Advantages and disadvantages 2. Solar powered vehicle • Introduction • Procedures ➢ Photo – voltaic cell ➢ Electrical system ➢ Mechanical system • Solar arrays
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UNIVERSITY OF CAMBRIDGE INTERNATIONAL EXAMINATIONS General Certificate of Education Ordinary Level CHEMISTRY Paper 1 Multiple Choice May/June 2005 1 hour Additional Materials: Multiple Choice Answer Sheet Soft clean eraser Soft pencil (type B or HB is recommended) 5070/01 w w w e tr .X m eP e ap .c rs om READ THESE INSTRUCTIONS FIRST Write in soft pencil. Do not use staples‚ paper clips‚ highlighters‚ glue or correction fluid. Write your name‚ Centre number and candidate number on the answer
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Unit operations and unit processes http://www.mine-engineer.com/ • At the end of this unit you should be able to: a. List the various reasons for undertaking size reduction and enlargement in the chemical industry b. Describe the operation principles of some size reduction equipment and size enlargement equipment c. Explain how industrial materials can be separated on the basis of their magnetic‚ electrostatic‚ hydrophobic and volatility differences respectively d. Discuss various organic unit
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Pre-Feasibility Study Beauty Clinic Small and Medium Enterprise Development Authority Government of Pakistan www.smeda.org.pk HEAD OFFICE 6th Floor LDA Plaza Egerton Road‚ Lahore Tel 111 111 456‚ Fax: 6304926-7 Website www.smeda.org.pk Helpdesk@smeda.org.pk REGIONAL OFFICE PUNJAB 1 INTRODUCTION........................................................................................................4 1.1 Project Brief ...................................................................
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Science‚ Medicine & Technology – Lecture 2 14th September‚ 2012 Global Warming – Paul Waithe * Differences between climate change & global warming: Global warming is the overall increase in the earth’s temperature. Climate change may be in either direction. For instance; more hurricanes‚ more wind etc. Comprehensive way at looking at weather patterns. * Climate change over the past century is directly linked to global warming. * Global warming could result in the world
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supply is located on the surface with connection to the diver/welder via cables and hoses. In wet welding MMA (manual metal arc welding) is used. Power Supply used : DC Polarity : -ve polarity When DC is used with +ve polarity‚ electrolysis will take place and cause rapid deterioration of any metallic components in the electrode holder. For wet welding AC is not used on account of electrical safety and difficulty in maintaining an arc underwater. Power Supply Electrode Holder
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Science Study Notes An electrically uncharged object is neutral. Conduction is not a method of charging an object. If electric charged stay in one spot‚ they are said to be static. In charging by induction‚ when a negatively charged rod is brought near a metal leaf electroscope the electrons in the electroscope move away from the rod. A statement that is not part of the Law of Electric Charges is that neutral objects are attracted to uncharged objects. The purpose of a GFCI is to protect people from
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Chemical Reactions and Equations Chemical Reaction: The transformation of chemical substance into another chemical substance is known as Chemical Reaction. For example: rusting of iron‚ setting of milk into curd‚ digestion of food‚ respiration‚ etc. In chemical reaction new substance is formed which is completely different in properties from the original substance‚ so in a chemical reaction chemical change takes place. Following are the signs of chemical reaction: (a) Change of state of substance
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