May 17, 2016

A few Seconds and Thousands of Eggs

Short story by Yoel Yaron

It is said that when people fall to their death, their entire life flashes before their eyes. 

Well, if that's what they say, then that's what they say. As for me, I'm preoccupied at this very moment with one simple question: how many seconds do I have left before I crash to my death?

Question #3: An object, initially at rest, falls freely from an altitude of 400 meters. How long does it take the object to hit the ground? Disregard the effect of air resistance.
I stared blankly at the exam paper, trying in vain to remember the formula. All I managed to recall was that the acceleration of gravity is equal to 9.81 meters per second squared, whatever that means (Never could figure out how for God's sake can you square a second). I also failed to solve the first two questions.

Such a student was I, inattentive during lessons, neglecting homework, failing to prepare for exams. At the end of ninth grade I quit school. Who cares anyway about physics, math, history, grammar and all that scholarly stuff?

And now … fear. Not just fear, horror! For years, since early childhood, I had never experienced such a feeling. My entire body is covered with cold sweat.
Does my life flash before my eyes? Come on! Life indeed!

I was brought up in a so-called normative home, one of five kids. My siblings, encouraged by our parents, all excelled in their studies and proceeded to acquire good jobs. Me, I dropped out of school after flunking math and physics. No regrets! Nothing held my interest except for tightrope walking. I had started to practice as a small child to my parents' dismay. All their efforts to dissuade me failed. I was entirely self-confident and fearless. In my youth I used to impress my companions by nonchalantly crossing the distance between two tall buildings on a rope stretched between their roofs. I was literally intoxicated by the thrill, the success and the admiration that came my way. I practiced day in and day out for hours and hours until my hobby turned into a well-paid profession.

Now and then I volunteered to take part in fund-raising events for charity and so I did on the present occasion when I offered to walk a tight rope between two skyscrapers in Manhattan, stretched four hundred meters above ground. After some deliberations, the NY municipal authorities consented to license my performance, provided that I make sure to take the proper safety measures. As a precaution, the local safety department temporarily proclaimed the road segment under which the rope was stretched to be a danger area. Police officers were stationed at both ends to keep the zone clear of vehicle and pedestrian traffic while the act was on.

In defiance to the agreement I decided to waive all safety measures, basing my confidence on my years of experience. However, when I was midway along the rope, my attention and concentration were distracted by a commotion down on the road. Two police officers were yelling at the top of their voices while chasing on foot a big truck whose driver started to drive  it  after loading merchandise inside the supposedly evacuated area, apparently unaware of the blockade . I made the catastrophic mistake of looking down, resulting in the loss of my equilibrium. Swaying desperately from side to side, I tried in vain to regain stability.

Now I'm in the air, racking my brain for the formula. Let's see now, speed builds up so that at each moment during the descent it is equal to the product of gravitational acceleration by the time that has passed since the descent began. Makes sense, right? Great, but how in heavens do I proceed? I'm plunging a total of 400 meters with a speed that keeps increasing according to gravitational acceleration, so how much time do I have to complete the fall? In short, how much longer can I expect to live?
I shut my eyes. My body is soaked with perspiration. Wet. Sticky. What's this viscidity, blood? Hey, am I still alive?

Darkness surrounds me.

I open my eyes in a lighted room. I'm lying on a bed covered up to my chin with a white linen sheet.
"Awake at last! How do you feel?"
A nurse in a greenish robe smiles at me. Behind her I notice some men and women, news reporters I guess by the microphones and the cameras held in their hands.
"What's going on", I ask the nurse. "Where am I?"
"You passed out! Terrific luck you had, nothing but a few superficial bruises!"
"I don't get it, you mean I am alive?"
"Sure! Thanks to the driver". The nurse points to a lean fellow in a dungaree overall that stands beside her. "He saved your life!"
"I still don't get it. Who are you?" I ask the man in the dungarees. "How did you save me?"
"I drove the truck directly under you when you fell down. Nobody told me the way was closed for traffic. Now the cargo is lost and someone will have to pay for all those broken eggs".
"Eggs? What eggs? What are you talking about?"
"Man, what's the matter with you? Haven't you noticed that you landed on the eggs that I transported on my truck? Thousands of eggs, all crushed by your body and the canvas cover torn too when you fell through it. Lucky you, you missed the iron arches that supported the canvas".

All of a sudden, I could see it clearly. To calculate the distance of descent, in other words the height, you take the average speed which is half the final speed and multiply it by the total time of descent. To calculate the final speed you multiply the constant of gravitational acceleration by the total time. Combining the two calculations, you find that the height equals half the product of the gravitational acceleration by the square of the total time of descent.

But hold it! Time is the unknown factor whereas the height is known, so what have we accomplished? Let's see now! Suppose we reverse the approach, meaning that to find the time we need to divide the height by the gravitational acceleration, multiply the quotient by two and calculate the square root of the result.
Specifically, 400 divided by 9.81 and multiplied by 2 yields slightly more than 81, the square root of which is slightly more than 9. In short, the total time of descent from the altitude of 400 meters to the ground sums up to approximately nine seconds.

Ample time for a selfie, if only I had a smartphone on me!

Nine secs, that's all! For nine measly seconds I was expelled from high school!

Oh, and don't expect to ever again see me even getting near to a rope!

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