Today every student of science or engineering and even high school students come across this common word electronics. Students study just because it is part of academics, but some students at least 1 out of every 10 students wonder?
Where Did This Term ELECTRONICS come from?
why do we call it electronics?
To find the answer to this question let’s get into the time machine and travel 100 or 200 years back into the past. In the 19th century, to our surprise, there was no subject called electronics at all.
During this period all the research and experiments were carried out at the atomic level and no one actually knew that atoms can be broken down into smaller particles, something like electrons really existed Until 1887, a great scientist J J THOMSON through a series of experiments discovered that electrons existed and that electrons are negatively charged. This discovery was followed by the discovery of protons and neutrons by Rutherford and Chadwick respectively.
With this discovery, various scientists across the world started performing experiments at the subatomic level i.e at the electron level and the new field of Electronics was born. This study is used for designing various electronic circuits that exist today such as mobile phones etc.
The study at the subatomic level that is used to design electronic circuits and other electronic devices is called electronic engineering.
Electronics is a branch of physics, in fact, everything that we study under electronic engineering has its roots in physics. Since people all over the world are going deep into electronics research, electronics is today existing as an individual branch of studies with its own set of branches.
History and evolution of electronics
- In 1791 Luigi Galvani: Professor of anatomy (university of bologna), with the help of series of experiments, showed the presence of electricity in animals (specifical frogs).
- In 1799 Charles coulomb: One famous scientist of the 18th century, demonstrated that there existed a force between any two charges, this force could be either attractive force or repulsive force, and this force is also influenced by the distance of separation between the two charges.
- In 1799 Allessandro Volta: An Italian scientist credited with the invention of the battery. He was the first to develop a battery known as the voltaic cell that could produce electricity due to a chemical reaction.
- In 1820, Hans Christian oersted showed that a magnetic field is associated whenever current flows through a conductor. To demonstrate this effect, he connects a copper wire to the terminals of a battery and a switch and placed a magnetic compass near the wire. When the switch was closed current started flowing in the wire and a deflection was seen in the compass indicating that the current-carrying conductor has an associated magnetic field.
- In 1827 George Simon Ohm, a germen physicist derived the relation between the voltage applied (V), the current (I), and the resistance of a circuit. This is the famous and the most basic law of Ohm’s law. It is given as V=IR.
- In 1831 Michael Faraday, a British scientist after the discovery by Oersted that a magnetic field is associated with the conductor carrying current, Faraday through a series of experiments discovered that vice versa is possible i.e. current can be generated by using a time-varying magnetic field. This phenomenon was termed Electromagnetic induction which is the basic underlying principle of the working of generators.
- In 1864 James Clerk Maxwell, A British Physicist developed the electromagnetic field equations that today is referred to as Maxwell’s equations. He also formulated an important theory known as the electromagnetic theory of light, which told that electromagnetic waves travel in free space at the speed of light.
- In 1888 Heinrich Hertz, Based on the predictions of Maxwell’s electromagnetic theory wanted to experimentally verify the theory. He performed various experiments according to Maxwell’s theory and successfully demonstrated to the world the effect of electromagnetic radiation through space.
- In 1895 Guglielmo Marconi put together the predictions of Maxwell and the experiments of Hertz to send electromagnetic signals through space and was successful in setting up the first transatlantic wireless communication system.
- In 1948, William Schockley, John Bardeen, and Watter Brattain developed the transistor.
- Nikola Tesla: One great scientist without whom our today’s world would have been dark. Yes, he invented alternating current (Popularly known as AC) and gave light to the world. He also has his name Tesla as the unit of magnetic field added to his credit.
Introduction and need for school electronics
Every semester I get to teach students from various fields, and either they join the electronics course out of curiosity(rarely), or the academic program makes it mandatory to take up the course on basic electronics. Most of the instructors or teachers who teach basic electronics get many questions in the first class itself.
The most common question that is thrown out in the first class is
“I am a mechanical Engg student, Why is it that I should study electronics? Why is it made mandatory? “
The above question is just one instance, Its not mechanical engineering always I do get the same question from students from different background
Today, Our life is so much dependent on electronics that my friend’s son says, “I can live without food for a day but not without my cellphone.” The universities conducting the courses do not want to burden students, but it has become necessary to create awareness among the students of how electronics in the world works.
Another student continues the question.”But why, I know how to use a cell phone, and I am not interested in knowing how it works.”
Let me give you an instance where this knowledge on basic electronics would have saved the day.
Here Fred, an educated but electronics illiterate student, visits a store to buy a new cell phone.
Fred: I need a new cell phone with a good camera and long battery life without frequent charging.
Salesman: Sure, sir, Regarding the battery life, what is the number of standby hours(no. of hours the phone will be switched ON but not used)and Talktime hours(hours that you can continuously speak without plugging in for a charge)you need?
“Salesman uses this question to test if he can fool you. I agree not all salesman try to cheat there are genuine ones as well this is just an instance”.
Fred: I have this old phone of mine which beeps ‘low battery’ every 4 hours so I need a good phone which will not have this problem.
Salesman: I have the right cell phone for you which has just arrived, built on the latest technology and you can use it for a week without plugging it for a charge.
He shows the standby hours printed on the box that says 400 hours.
Fred: Wow !! Fantastic I will buy one.
The salesman makes a good profit, and Fred fails to see the banner in the store “goods once sold will not be taken back.” If Fred had some basic knowledge of electronics, he would have definitely wondered, ‘How is it possible for a battery that small to run for weeks and without charging ?’
I would not say that all the students should be an expert in electronics, but some basics will definitely come in handy because the world is filled with electronics all around. At school electronics, we will try our best to express the points assuming you know nothing of electronics.
We will also learn in more detail about Digital Electronics, its importance and the impact it has in our daily life.