Skip to main content

We show degree on centigrade and not show on kelvin why??..what is reason behind it??


The Kelvin temperature scale is sometimes called the absolute temperature scale, especially in older books. It was developed byWilliam Thomson, also known as Lord Kelvin, in 1848. A Kelvin degree is the same size as a Centigrade degree. This temperature scale however uses absolute zero, rather than the freezing point of water, as the zero point. In this temperature scale water freezes at 273.15 Kelvins and boils at 373.15 Kelvins. The Kelvin temperature scale should be used in thermodynamic calculations. Its principle difference is that kelvin measurements, written as K have a much lower starting point: 0K or 0 Kelvin (note the absence of the degree symbol °).

It bears additional mention that kelvins are not measured by degrees. They were considered so until 1968, when the 13th General Conference on Weights and Measures determined to drop the degree reference. This decision was made because Thomson’s measurement referred to an absolute and specific temperature (where no heat energy exists). Celsius, conversely, uses the point of reference of water freezing at the bottom of its scale, and this doesn’t accurately account for heat energy left in the water at this point (273.15 K). Instead, these temperature units are thought of as kelvins. When you measure something by Celsius, for example the boiling point of water, you are measuring in degrees (approximately 100° C). The boiling point of water on Thomson’s scale is approximately 373 kelvins or written as 373 K.

There are some important marking points for Thomson’s scale. Absolute zero is 0 K, and the triple point of water, where water can exist as gas, liquid and solid is 273.16 K (.01° C or 32.018° F). The melting point of ice, 0° C or 32°F, is 273.15 K. The boiling point of water, approximately 100° C or 212° F, is exactly 373.1339 K.

The scientific community often uses kelvin and Celsius measurements interchangeably or at the same time. You may see data on temperature given both a C degrees measurement and a kelvin measurement. This is especially the case when discussing heat energy units between the melting point of ice and absolute zero.


Comments

Popular posts from this blog

COMMON COLLECTOR CONFIGURATION OF A TRANSISTOR

COMMON COLLECTOR CONNECTION

In  this  configuration  the  input  is  applied  between the  base  and  the  collector and  the  output  is  taken  from  the  collector  and  the  emitter.  Here  the  collector  is common to both the input and the output circuits as shown in Fig.

  Common Collector Transistor Circuit

In  common  collector  configuration  the  input  current  is  the  base current  IB  and  the output current is the emitter current IE. The ratio of change in emitter current to the  change in the base current is called current amplification factor.

It is represented by


COMMON COLLECTOR CIRCUIT

A test  circuit  for determining the  static characteristic  of an NPN transistor is shown in Fig. In this circuit the collector is common to both the input and the output circuits.   To   measure   the   base   and   the   emitter   currents,   milli   ammeters   are connected in series with the base and the emitter circuits. Voltmeters are connected   across the input an…

XII - Ch# 12 : Electrostatics :Solved Numericals

Solution Manual : Mathematical methods for physicists 5th edition Arfken and Weber

Download
DJ VU Reader
Book Description Now in its 7th edition, Mathematical Methods for Physicists continues to provide all the mathematical methods that aspiring scientists and engineers are likely to encounter as students and beginning researchers. This bestselling text provides mathematical relations and their proofs essential to the study of physics and related fields. While retaining the key features of the 6th edition, the new edition provides a more careful balance of explanation, theory, and examples. Taking a problem-solving-skills approach to incorporating theorems with applications, the book's improved focus will help students succeed throughout their academic careers and well into their professions. Some notable enhancements include more refined and focused content in important topics, improved organization, updated notations, extensive explanations and intuitive exercise sets, a wider range of problem solutions, improvement in the placement, and a wider ra…