Category Archives: Science

The Miracle of the Car – Part Four – The Miracle of Oil

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THE MIRACLE OF OIL – Bringing Light Where there was Darkness, Bringing Warmth where there was Cold, Shrinking Time and Space
1.) In this era of climate change, it’s easy to forget the miracle of oil – how it brought light where there was darkness, warmth where there was cold, how it shrunk time and space to bring needed goods to the needy faster and cheaper than before
2.) Energy density is at the heart of this remarkable story: gasoline has an energy density of 46 (MJ/kg) versus 16 for wood and 24 for coal. (And just for a fun comparison: 3.9 MM for uranium 235).
3.) The eye-popping, page-turning history of how oil came to supplant coal and wood is told in one of the greatest books of the last 50 years: The Prize by Daniel Yergin.
4.) And, thankfully, this long, engrossing book was turned into a fantastic PBS documentary, narrated by Donald Sutherland.
I INVITE YOU TO READ OR TAKE A LISTEN!
https://en.wikipedia.org/wiki/The_Prize:_The_Epic_Quest_for_Oil,_Money,_and_Power

The Miracle of the Car – Part Three – Transmission – boring? No way!

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1. When your car accelerates from 0 to  60 mph, your wheels turn from zero to 1000 revolutions per minute, but your engines crankshaft operates in a range of 800 to 6000 rpm. Gearing is necessary to coordinate them. This is the job of the transmission.
2. Gears trade torque for rotational speed the way a lever trades force for distance.
3. Flywheels are the part of the transmission that smoothes out the jerky pulses of the engine.
4. The clutch disengages the engine from the transmission when the car is still or gears are being changed.
5. In a front engine rear-wheel drive car the driveshaft connects the gearbox in the front to the differential in the back. The latter divides the force in half passing it on to each of the wheels, then increases the gear ratio by a factor of 4, and allows the two wheels to spin at different rates to negotiate a turn.
6. Driveshafts are hollow because paradoxically a hollow tube is stronger than a solid tube in bending and torsion.
7. Universal joints give drive shafts the necessary flexibility.
8. Other amazing parts of the transmission system are the dog clutch, the lay shaft, and the syncromesh which I will leave to others to explain the marvels of.

YOUR TURN– THE TRANSMISSION CHALLENGE: poets, musicians: please turn this amazing story into a sonnet, rap, ballad!

The Miracle of the Car – Part Two – The Seven Subsystems of the Internal Combustion Engine

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SHOULD EVERY 8TH GRADER KNOW WHAT THE SEVEN SUBSYSTEMS OF THE INTERNAL COMBUSTION ENGINE ARE?
Yes. From an ethical perspective nothing is more important in life than appreciating the world around you. That world includes both natural systems and engineered systems. Neither should be taken for granted. No engineered system is more ubiquitous
than the automobile. Nothing is more intriguing to children than cars. What a perfect way to teach science?
In Part One of this series on the car we discussed the miracle of 132 molecular bombs exploding per second under the hood. But this generates a huge amount of heat that must be dissipated through the cooling system (eg. coolant, radiator, fan), as well as a huge amount of exhaust which must be cleaned up in the catalytic converter and expelled through the tail pipe, and a huge amount of sound that must be muffled, a huge amount of friction that needs lubrication, a very precise opening and closing of valves that is accomplished by an ingenious contraption called a camshaft driven by a timing belt attached to the crankshaft, then it needs a very precise mix of fuel and air provided once by the carburetor and now by a fuel injection system, which must be ignited by a spark
plug jolted by high voltage from an electrical system which includes a battery, an alternator (a generator tied also to the crankshaft), and an induction coil (transformer) to boost the voltage. Alternatively, combustion can be achieved without a spark plug via compression alone (as in diesel engines).
A thing of beauty or what? Analogous to the orchestration of strings, winds, percussion, brass, vocalists. The work of thousands of nameless scientists, engineers, and tinkerers over generations. Honor them!
Next time: the miracle of the transmission system.
Experts, YOUR TURN: please correct, elaborate, elucidate.

What makes a car go? what should every 4th grader know? 8th grader? 12th grader? college graduate? what do you know?

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WHAT MAKES A CAR GO – THE CHALLENGE
Before you read any further, take out a piece of paper and write down your best explanation. Then grade yourself. Then date your answer and file it in a thematic binder labeled “Science and Engineering Journal.” This thematic journal will be a life-enhancing learning tool for the rest of  your life if you follow a discipline of asking yourself on a regular basis (say weekly, monthly) do I really understand how “x”works (eg. car, air conditioner, toilet), then test yourself with the writing challenge, then filling in the blanks by doing some research on the web and talking to someone that might know more about it. Then share the results with others.
EATING MY OWN COOKING – shorter and longer versions
Version #1 – The Miracle of the Internal Combustion Engine
One hundred and thirty two molecular bombs per second !!!!
Version #2 – The Miracle of the Automobile
Cars convert chemical energy of hydrocarbons into the mechanical energy of a rotating shaft
Version #3 – Elaboration
One hundred and thirty two very precisely controlled explosions per second generates
the energy that is then channeled to the wheels which exert a force on the pavement
that generates an equal and opposite reaction from the pavement that propels the
car forward.
More Specifics:
The Bomb: as an atom bomb splits an atom, a molecular bomb splits a molecule –
in this case molecules of carbon and hydrogen. For example, the combustion
of octane with air turns 2C8H18 + 25O2 into 16 CO2 +18H20 + Energy
The Four Stroke Cycle: induction, compression, power, exhaust –
can you visualize each? It’s a little miracle. And it’s called the
Otto cycle! History is weird: the auto cycle was developed by a guy
named Otto!
Camshaft, Crankshaft, Syncromesh, Dog Clutch, Universal Joints,
Planetary Gears: should every 4th grader, 8th grader, 12th grader
know how these components function? What better way to teach
science?
That’s enough for now. This is the first in a series on the Miracle of the Car.
Thesis: we take too many miracles of every day engineering for granted.
Recommended Reading: Stephen Resler, Everyday Engineering.
Experts: please correct, elaborate, elucidate.
YOUR TURN
Please share the coolest thing you learned this week related to science
or engineering.

Politicization kills conversation

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When the quest for truth slams into self-interest (in terms of professional
advancement or job security) or partisan loyalty, it’s likely to be bad
news for the former. Such is the sad state today when it comes to climate science.
A climate of finger pointing and name calling is stifling serious conversation.
“Whether the pitcher hits the stone, or the stone hits the pitcher, it’s going
to be bad for the pitcher.”

—Sancho Panza, Man from La Mancha (Don Quixote, Miguel de Cervantes)

The Plate Tectonics Revolution

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As late as the 1960s, US geology textbooks explained mountains using the principle of isostatic equilibrium according to which mountains are like icebergs floating on land. As icebergs have a smaller section above the surface and a deeper part beneath the surface, so with mountains.

Changes in mountains were a function of vertical, local forces.

The platetectonics revolution began with Alfred Wegner’s theory of continental drift. He noticed the similar shape of the South American and African coasts and gathered data showing that on opposite sides of the Atlantic similar species of animal and similar mineral deposits were found. He postulated that the continents had drifted apart.

But his theories were considered speculative and rejected by most scientists because he lacked any explanation for the force that could account for such drift.

The next line of evidence bolstering Wegner’s theory was the discovery of the mid-Atlantic ridge as the result of sonar searches for German submarines during World War II. Prior to the War it was assumed that the ocean floor was a flat featureless plain, “the abyssal plain.”

Far from it. The mid-Atlantic ridge is the largest single feature on the planet earth.

The next set of data leading toward the platetectonic revolution was the study of the ages of the islands in the Atlantic. It turned out there was a linear relationship between the age of the island and the distance from the ridge in a symmetrical relationship on either side of the ridge.

Finally came the discovery of a pattern of regular reversal of the magnetic field frozen in the rock on either side of the mid-Atlantic ridge.

 

Best science experiment selection algorithm?

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The best science experiments to teach children are ones that involve the least equipment. The very best involve no more than their own bodies. Repetition is the key to learning anything. The less equipment the easier to repeat and share with others. Example: stand up, change the angle of your head. What happens to the rest of your body? Why?

What is your favorite science experiment selection algorithm?