vacuum. In the electron microscope and the ion microscope‚ microdischarges due to applying high voltage to electrodes sometime occur‚ resulting in deterioration of image quality. Microdischarges are related with the gas molecules on the surfaces of insulators and electrodes. For many scientific instruments such as the electron microscope‚ a very clean‚ ultrahigh vacuum is necessary in the vicinity of the
Premium Vacuum Vacuum pump Pressure
Class X‚ PHYSICS‚ "Electricity" Definitions 1. Insulators Those material objects that do not allow charge to pass through them are known as Insulators or non-conductors. 2. Conductors Those material objects that allow the charge to pass through them are called conductors. 3. Semi Conductors Those material objects that allow some charge to pass through them are called Semi-Conductors. 4. Free Electron Those electrons that are loosely bound by their atom and can move freely
Premium Electric charge Electricity Electric current
solution Dissolve in water and form acidic solution pH of aqueous solution 14 9 7 7 1 3 Acid-base nature Basic Basic Amphoteric Acidic Acidic Acidic Conductivity of liquid Conductor Conductor Conductor Insulator Insulator Insulator Solubility in hexane Insoluble Insoluble Insoluble Soluble Soluble Soluble Structure Giant ionic structure Giant ionic structure Ionic with covalent character Giant covalent structure Simple molecular structure
Premium Ionic bond Oxygen Oxide
LIGHTNING ARRESTER INTRODUCTION A lightning arrester is a device used on electrical power systems and telecommunications systems to protect the insulation and conductors of the system from the damaging effects of lightning. The typical lightning arrester has a high-voltage terminal and a ground terminal. When a lightning surge (or switching surge‚ which is very similar) travels along the power line to the arrester‚ the current from the surge is diverted through the arrestor‚ in most cases to
Premium Lightning
Introduction to Materials Science and Engineering Chapter 1. Introduction Hyung-Joon Shin School of Mechanical and Advanced Materials Engineering Ulsan National Institute of Science and Technology (UNIST) UNIST 2011 Spring AME20201 Introduction • Course Objective: Introduce fundamental concepts in Materials Science • You will learn about: • material structure • how structure dictates properties • how processing can change structure the final grade. Please actively take part in the class
Premium Materials science
Radio 25 Basic Electrical Principles • Conductors - keep loose grip on their electrons and allow electrons to move freely. Metals are usually good conductors. • Insulators - keep close hold of their electrons and do not allow free movement of electrons. Glass‚ wood‚ plastic‚ mica‚ fiberglass and air are good insulators. • Electromotive Force (EMF) is the force that moves electrons through conductors. Its unit of measure is the Volt. Think of it as pressure. • Voltage Source - has two
Premium Resistor Electric current Volt
REVIEW doi:10.1038/nature10676 Multigate transistors as the future of classical metal–oxide–semiconductor field-effect transistors Isabelle Ferain1‚ Cynthia A. Colinge1 & Jean-Pierre Colinge1 For more than four decades‚ transistors have been shrinking exponentially in size‚ and therefore the number of transistors in a single microelectronic chip has been increasing exponentially. Such an increase in packing density was made possible by continually shrinking the metal–oxide–semiconductor
Premium MOSFET
sheath‚ both usually of thin copper wire. The inner insulator‚ also called the dielectric‚ has a significant effect on the cable’s properties‚ such as its characteristic impedance and its attenuation. The dielectric may be solid or perforated with air spaces. Connections to the ends of coaxial cables are usually made with RF connectors. Radio-grade flexible coaxial cable. A: outer plastic sheath B: copper screen C: inner dielectric insulator D: copper core There are two types of coaxial cables:
Premium Ethernet Coaxial cable
Chapter-14 Comparative salient feature of OHE of DMRC & Indian Railway 15.1 IMPORTANT DMRC OHE PARAMETERS (Rail Corridor) S.N. | Parameters | Specification as per DMRC | Specification as per Indian Railway | 1 | Normal height of contact wire at support point for regulated OHE | 5.00 mtr (Presag -1000th part of span length) | 5.50 mtr | 2 | Normal height of contact wire at support point for unregulated OHE | 5.15 mtr | 5.70 mtr | 3 | Minimum height of contact wire at loco inspection
Premium Length Maxima and minima Orders of magnitude
In Antarctica it can get as cold as -50°C this is because the sun is aimed at a shallow angle towards Antarctica this means that there is not a lot of sunlight that hits Antarctica‚ the sun that does hit Antarctica is either reflected off the shiny white ice and the heat energy is sent into space or the heat energy from the sun’s rays is absorbed by water vapour and dust‚ the sunlights energy is also spread across a large area therefore there is a large surface area to volume ratio. Emperor penguins
Premium Bird March of the Penguins Ocean