The Physics Of Fruit

datsun_b210_1_76Sir Isaac Newton had something to say about an apple that was a victim of gravity. My high school physics professor was even better. He taught us all about velocity, force, inertia, vectors and much of what he had to teach us about physics with the help of a very ripe persimmon . . . and an insipid green 1976 Datsun B210.

I was reminded about these lessons a few years ago while Brent and I were in his old neighborhood in Los Angles. He pointed out an old burnt-orange Caprice that was in remarkably good condition. It had less than the typical wear and tear for a car that was nearly as old as we were. Brent pointed out a nearly imperceptible but specific dent in the driver side tail flank, and explained that it was made by a hard under-ripe peach. I did not need to ask how a green peach had attained sufficient force to cause such damage. I grew up in the Santa Clara Valley, where we all know the joy of attacking cars with fruit.

Most of our ammunition was apricots in various stages of ripeness. While in season, the orchard provided an unlimited supply. While they were out of season, we took what we could get from other fruit trees. Winter was meager; but just before 1977 became 1978, we discovered the gloriously humongous and squishy fruit of the ‘Hachiya’ persimmon tree in a neighbor’s front yard. Each fruit had the destructive force of a large ‘Marsh’ grapefruit, but with a squish factor of tapioca pudding! We had never seen anything like it!

Our first victims probably did not know what hit them. They probably heard the mild thuds on their cars, and drove home believing that they had been hit with the typical and mess-less lemons or oranges that are available in winter. Only after parking their shiny cars and getting out did they witness the horror or ‘Hachiya’ persimmon! Perhaps that is how ‘Hachiya’ got its name. It sounds Japanese for something someone would say in response to such a hideous mess. “Hachiya! What happened to my Mitsubishi?!” I do not know if Mitsubishi was around back then. Most of our targets were big American cars.

Then one day, we got a more challenging and more appropriately Japanese victim; a bland green Datsun B210. It was a smaller and speedier target than what we were accustomed to. Our small herd of neighborhood boys ran out to greet it; but then something unexpected happened. The car stopped. The red-headed leprechaun driving it saw us coming and just stopped there before the first persimmon took flight.

We were baffled. The other boys dropped their fruit and ran. I was too annoyed. I did not want to waste the big fruit that the persimmon tree had put so much work into. So, . . . I threw it. It made first contact on the right side of the windshield, and slid its sloppy ripe goo over most of the windshield to the driver’s side. Yes, it was glorious!

I stood there briefly in awe before I realized that the driver of the car was just glaring back at me . . . with the LOOK! Yes, it was the look; the look that said, “If I did not have these short leprechaun legs, I would run after you and beat you into the mud!”. Then I ran off to join the other boys, believing that was the end of it. I occasionally saw the Datusn around the neighborhood afterward, but did not think much of it, unless the leprechaun driving it happened to glare menacingly back at me.

We started high school a few years later. Part way through the first day, I got to my physics class just before the teacher arrived. I was already seated when he walked in, and glared right at me. Yes, it was HIM; the leprechaun! For the first time ever, I saw him smile. He did not have long fangs dripping with blood, but he was terrifying nonetheless. This was going to be a long nine months!

It wasn’t that bad. In fact, the leprechaun was one of many excellent professors at my high school. We all liked him. He did have an odd way with word problems though; you know, those situations involving ‘object A’ and ‘object B’. We had word problems like, “If object ‘persimmon’ weighs .75 pounds and is traveling east at 25 mph, and object ‘Datsun’ weighs 2,000 pounds and is traveling southwest at 25 mph, how much force will object ‘persimmon’ exert against object ‘Datsun’ when they collide?”.