What is heat? What makes us feel it? Why do we feel that the temperature of a metallic object is higher than a non metallic one, when both are kept under the sun?

Such questions have led to the development of the field called thermodynamics. The question that we started with--- what will be 30 degrees Celsius converted to Fahrenheit? --- can only be answered once we have gone to the root of this topic.

Since the appearance of human beings on the face of the earth, heat has always been their friend. But it took lots of time to actually be able to measure heat. They got a clue, when they first saw some changes in physical quantities, when they heated objects. Among them the most noteworthy is change in length and volume. Almost everyone noticed the change in length or volume, associated with heating process. Measuring temperature became easy, when humans realized that if they can find the proportionality constant between the length of a body and its temperature, then they would have built a thermometer. And the best of such substance was mercury, since it expanded enough to show notable changes with change in little temperature.

However, there is yet a long way to go. In the nineteenth century scientists found link between heat and energy. And that led to better understanding of heat and temperature. It became clear to human that heat is yet another form of energy. And more the heat produced in a mechanical machine greater is the inefficiency of the machine. This little observed truth led to the understanding that perhaps the energy supplied to the machine is getting lost as heat through friction, wear and tear. Further more, further clues came from the fact that when a gas was compressed in a closed piston, the gas got heated up, even though no heat was supplied to it. This led to the final understanding that heat was the result of the energy that was supplied in form of force to a body.

Once this was understood machines became more and more sophisticated, and of course more reliable. Yet that was not enough. The study of this simple innocent branch of science led to the development of a very baffling topic called the entropy. Through which Boltzmann showed that every system was moving towards inconsistency. At his time, he was not accepted, and even worse, his theory was not respected. But now his theories are famous through out the world.

Now let's come back to our question. What will be 30 degrees Celsius converted to Fahrenheit? To understand that lets first understand Celsius and Fahrenheit. Ice freezes at zero degrees Celsius. And boils at hundred degrees Celsius. With that system, we can divide all the temperatures in between into 100 divisions.

The Fahrenheit scale comes from the temperature of body. Where the temperature of the body is set to be 100. This scale is named after the discoverer. Apart from these two scales there is the absolute scale. The absolute scale is developed on the basis that at -273 degree Celsius, all molecular activity stops. The absolute scale is much more sophisticated and is more scientific. The difference between two marks in a Celsius scale and a Kelvin or what we call the absolute scale is the same.

Now let's come to the show down. How do we convert Celsius to Fahrenheit? There is an easy formula

C = 5 / 9 ( F - 32 )

So all we need to do is put the value in Celsius in place of C and solve the algebraic equation, and we will get the value in Fahrenheit, by solving for F

30 = 5 / 9 ( F - 32 )

= >[( 30 x 9 ) / 5 ] + 32 = F

=> F = 86 ºF

The use of Fahrenheit is almost out dated in most part of the world, except in the use of doctor's thermometer. However, USA quite stubbornly still uses it. And being a foreigner at USA it's quite a pain at the neck with these ºF air conditioners.