Learning Outside of Formal Education

 

Learning Outside of Formal Education

That is truly stupid of me. Education is education, the enterprise of learning. How can there be a “formal” category, and its opposite “non-formal”? But, believe me, there is one.

Sometime in the 1990s, I wondered for long how Nescafe said that its instant coffee granules are freeze dried. You get wet when you get frozen (or almost) at higher latitudes in winter. Then, how can Nescafe freeze dry its coffee granules?

One evening as I was sitting late in office and pretending to work, I suddenly thought of the natural geyser in the Yellowstone National Park in the US. I knew how the geyser erupts in about 90 minute intervals, give or take a few minutes. I had heard about, analyzed and accepted the mechanism, superheated water bubbling up through a column of water above that level, and spewing out a fountain of hot water and steam.

I merely asked myself what would happen if instead of heating the water, we cooled it to very low temperatures. I knew the difference between boiling and evaporation (unfortunately, our teachers of physics in my engineering undergraduate courses, while explaining both boiling and evaporation did not analyze them side by side to locate the source of the difference). If I were to tell you that evaporation is a cooling process, you would come to me with your sword drawn out of its sheath.

Be patient. You do say that water in the kettle heats up on its way to boiling. Likewise, if only a little thought is directed towards evaporation, you would find the water body cools. I will explain further.

All the water molecules are not travelling at the same speed in the water body as indicated by its temperature. Some travel slower, and some faster. The assessed average is the temperature (why you need to keep your thermometer under your tongue for two minutes). If near the surface, a water molecule moving at an appropriate speed and angle with respect to the surface hits the boundary, it would overcome surface tension forces and leave the water body, leaving it with high energy of motion. Therefore, voila! the average temperature of the water body reduces, it is cooled.

When the wet coffee granules are put in a container and air is sucked out, the fast moving water molecules are also released from the surface and out they go. The temperature of the granular mass is reduced. Just keep the process on, ALL the water molecules become sufficiently fast moving ones and are sucked out. Now, the coffee granules are frozen and bone dry! This is the process of freeze drying! While heat maybe added, in principle and if one had enough time, it is not essential.

Now comes the tenuous analogy with the Old Faithful. Some of the water (steam after condensation in the atmosphere as the fountain shoots up quite high) seeps through the porous sand around and occupies the vacated spaces at the top. Water at the bottom of the column gets heated by the energy from the earth but is unable to rise up through the water above. It gets superheated. When the threshold is reached, the pressure above is no barrier for the superheated water. The Old Faithful becomes newly and again faithful and erupts.

I was asked by a faculty member whether ocean waves are longitudinal waves. Immediate came my answer, “Of course not. They are transverse waves.” “Then, why do we have waves coming on to the beach and receding? Shouldn’t the waves be just like waves in a rope when jiggled?” That question must have stumped me, but did not, as the detailed image of the waves formed in my mind, giving me the necessary clue. No one had even mentioned this phenomenon to me till then, honest.

As transverse waves in deeper water propagate and approach the shallower waters near the shore, they gradually take on the characteristics of longitudinal waves.

 Voila! I have not only enjoyed waves lapping at my feet and up to calf level, I also knew why they did that. I do not know which physicist it was who boastfully remarked to his girlfriend that he was the only one who knew why the stars shine, while sitting in a beach on a chilly, clear night! Alas, no such luck for me.

It was said that if Richard Feynman were asked a question why such and such a thing happened, he would wonder how light would behave under those conditions. I have one situation where I was a faux Feynman! In a particular chapter in mechanics, as an equivalence of the phenomenon of refraction of light, I posed and solved a situation where a swimmer is struggling in water and a lifeguard is perched at a distance from the shore, but displaced sidewise from the swimmer. After giving all the required parameters, I solved the problem, stating first what the students have studied in high school about refraction of light: ratio of speed of light in two different media. I used the same principle in the problem posed and got the correct answer (students checked the answer using a different method.

In a PG course, taking an explanation given in a book (referred by students only for the problems it contained and not the explanations given), I explained the concept of buckling of a rectangular plate with different edge conditions along the loaded edges. I sketched the buckled shape using at least two differently colored pieces of chalk. But, no go, with the students. All they wanted were equations. Likewise I explained how the ratio of the sides affects the critical load. Same response.

The immediately preceding instance is one in which I did not take recourse to any analogy or a possibly related phenomenon. It was purely analytical. What I learned is no matter how and what the teacher teaches, students can look at the material only through the prism of grades. Formal or non-formal does not matter. But to soothe my own conscience, if I were to teach any more (zero chance), I would not change. I am as adamant as the students are!

To end this long post, it is my belief, only belief, that things learned non-formally stay with you, and with the others through you, even if you are not a teacher in an academic institution. Formal education leaves you when you leave a strait-jacketed path. And, in my books, this scores higher.

Any engineer, even after getting her MBA and is a well recompensed financial analyst,  looking at Old Faithful gush forth high and mighty, would reach for her cup of Nescafe instant coffee!

Raghuram Ekambaram