Who was Joseph Fourier?

Joseph Fourier is a renowned name in the scientific world credit to Fourier series and Fourier transform. His work is useful to various problems in physics including (but not limited to) heat transfer and vibrations.

Apart from his scientific ventures, Fourier was also involved in French politics. He played a significant part in the French Revolution at his district and came to the notice of a young French revolutionary Napoleon Bonaparte.

Joseph Fourier was born on March 21, 1768 in Auxerre, France to a very poor family. He was orphaned at the age of nine. Fourier could not afford formal schooling as a result, however, he did receive an extensive training by the Church.

His exceptional mathematical prowess was recognized by those around. Fourier was appointed scientific advisor to Napoleon Bonaparte in 1798 at the age of 30. He was promoted by Napoleon to the post of governor in Southeastern France.

It was there, in his free time, that Fourier conducted experiments on heat transfer. In 1807, he submitted a paper on the same to Paris Institute and invented two important mathematical tools while doing so.

The first contribution is called Fourier series in his honor. The tool to make other functions by adding infinite sine (and/or cosine) waves. It was indeed a groundbreaking breakthrough at the time.

The second contribution was dimensional analysis i.e. an equation can be correct only if the dimensions match on both sides of the equality. This finds use in physics.

In the 1820s, Fourier made another contribution to math: finding real roots of polynomials. But, his major work in this decade was the discovery of and experiments on the greenhouse effect.

In 1827, Fourier published an article in which he claimed that the Earth's atmosphere might act as an insulator. This was his last major work as he died in 1830 aged 62.

10 Albert Einstein Quotes To Succeed In Life

Apart from making groundbreaking discoveries in physics, Albert Einstein also played the role of a motivational guru quite often. So, following are 10 Einstein quotes that will change your life.

1. Everyone sits in the prison of his own ideas; he must burst it open, and that in his youth, and try to test his ideas on reality. [Meaning: Don't keep delaying what you really want to do. Try it out for who knows what is possible?]

2. Joy in looking and comprehending is nature's most beautiful gift. Never lose a holy curiosity for it has its own reason for existing. [Meaning: Every child is born curious. Keep your mind open to new adventures.]

3. Try to become not a man of success, but try rather to become a man of value. Because, only a life lived for others is a life worthwhile. [Meaning: Our relationships are just as important as goals.]

4. Life is like riding a bicycle. In order to keep your balance you must keep moving. [Meaning: Enjoy the ride. Don't be afraid to fall.]

5. Don't think about why you question, simply don't stop questioning. Don't worry about what you can't answer, and don't try to explain what you can't know. [Meaning: Curiosity is a quality one must never let go of. Ask questions as they will lead you to life's answers.]

6. Blind obedience to authority is the greatest enemy of truth. [Meaning: Don't follow people blindly.]

7. The value of a college education is not the learning of many facts but the training of the mind to think. [Meaning: Learn how to think, not what to think.]

8. I never think of the future. It comes soon enough. [Meaning: Live in the moment. Act now.]

9. The mediocre mind is incapable of understanding the man who refuses to bow blindly to conventional prejudices and chooses instead to express his opinions courageously and honestly. [Meaning: Break the mould you were born into.]

10. If A is success in life, then A = x + y + z. Work is x, play is y and z is keeping your mouth shut. [Meaning: Work hard. Play hard. Stay humble.]

Who was Gustav Kirchhoff?

Most high school and engineering students know Gustav Kirchhoff by his namesake circuit laws. But there is more to him than that as we shall see. Gustav Kirchhoff was born on 12 March, 1824 in Prussia (now Germany).

Besides circuit laws, Kirchhoff is known for making pioneering contributions to spectroscopy. With scientist Robert Bunsen, he invented the spectroscope in its modern form. He used it to study the spectrum of the Sun.

In 1859, he showed that the Sun contained sodium apart from Hydrogen and Helium. His spectroscopic work earned him greater fame in his native country. Since 1990, a little over 100 years after his death, the Bunsen–Kirchhoff Award has been given for outstanding achievements in spectroscopy.

Now coming back to electricity. You will be amazed to know that Kirchhoff was only a student when he formulated the two circuit laws in 1845. It later became his doctoral dissertation as well. The two laws are as follows:

1. The algebraic sum of currents meeting at a point is zero.
2. The directed sum of the voltages around any closed loop is zero.

They can be used to solve many problems in physics and engineering. Let's have a crack at it with a simple example.

Since (i) the sum of currents at a point must be zero and (ii) currents i1 and i2 are incoming (positive) and i3 and i4 (negative) are outgoing...therefore: 3+9-5-i3=0. This gives i3=7 amp.

That was current law in its simplest form. But combined with voltage law they can be used to solve very complicated circuits.

Apart from spectroscopy and engineering, Kirchhoff made equally important contribution to the field of thermochemistry. In 1858, he gave a law: The overall enthalpy of the reaction will change if the increase in the enthalpy of products and reactants is different.

In 1860, Kirchhoff coined the term black-body radiation and postulated the existence of a perfect black-body, an object that absorbs all the incoming light and reflects none. His studies were used by Max Planck to formulate the Planck's law in 1900.

Although Kirchhoff has become most widely known for his circuit laws but you can realize now how important his other findings were. To the fields of spectroscopy and thermodynamics. Gustav Kirchhoff was a proper genius.