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The Perpetual Motion Club

Page 4

by Sue Lange


  Elsa stopped tapping on her teeth and sat up, folding her arms on the desk. It occurred to her that perhaps other students around school might need help with a FutureWorld project. Maybe someone that wasn’t so scientifically inclined. Someone who’d never had a chance to think deeply about tech and geekery because he was busy doing something else. Like sports for instance. Like basketball perhaps. Slice.

  “The date’s been fixed for May 29 and it’s time for committees to form and decisions to be made,” Jerome said, jarring Elsa out of her thoughts.

  The announcement unfroze the other senior members out of their own thoughts as well. They began a brisk discussion of the necessary committees. Someone was needed to run the judging, and someone else for logistics. Who could be a liaison with the school authorities to determine what would and wouldn’t be allowed? Who would design the web page? Send out text messages during the event for live on the spot coverage? Program the robot greeters with the correct welcome banter and event maps? Jerome assigned a member of the Society to each post and then discovered that no one was left to actually be on the committees.

  Mr. Brown laughed it off. “That will make the committee meetings fairly short, eh?” he said.

  Everyone gave quiet little “huhs” in recognition of his joke. Their response pleased him.

  Then came the time for the initiation of new members. The mood brightened considerably when they realized new members meant fresh blood for the just-formed committees.

  Ten juniors filed to the front of the room and assembled themselves before the crowd. They each wore a big floppy beret, supposedly something Galileo or Da Vinci might have worn.

  Jerome led them in the recitation of the Society motto—“In knowledge there is truth.” And the pledge—“I promise to uphold the bylaws of the Northawken Society for scientific endeavor, and to live my life ever seeking truth and advancement of the human race.”

  Noble sentiments of course, and each initiate felt it deeply within his or her heart. Knowledge was their reason for existence. They had that insatiable Need To Know that drives every budding scientist. They’d had this need for as long as they could remember. They were tinkerers and wonderers, these initiates. They were concerned with the fate of humanity as promised by the last section of the pledge. And, of course, this Society membership would look good on their resumes and would probably ensure an easy entrance into an upper income bracket. These are not stupid people, these inductees.

  Elsa had seen some of the initiates in the hallways between classes, but she didn’t know any of them personally. She had no feelings one way or another about their aspirations and goals and so entertained no hopes for their success. She sat back in her seat and watched with a bored eye what seemed like a lot of mumbo jumbo. Soon she was clicking her teeth again.

  Mr. Brown began the final leg of the ceremony. “As you know, before our initiates can be full members, they must pass an initiation.” He moved to the Ferris wheel contraption sitting on the front desk. It was made out of erector set parts and certainly looked important. A sandwich board bearing a big fat Lego logo was propped up next to the gizmo, advertising Mattel as the sponsors for the evening’s demonstration.

  “This is a bit of history,” Mr. Brown said, waiting for the importance to sink in. He pointed to the contraption’s arms arrayed around a central pivot point. “Each arm has an elbow that allows it to fold inward. These little baskets of lead attached to the extreme ends are heavy and they force the arms to fold up as the wheel turns. The center of the wheel is attached to a post here, which holds the whole thing up.”

  The wheel faced the audience dead on so they could watch the turning and folding movement.

  “It’s a perpetual motion machine,” Mr. Brown said. “And is a testament to the follies of unscientific thought. The type of thinking that does not lead to viable end products, which, as we know, is the purpose of science.”

  Elsa pulled her fingers away from her mouth. “Bhaskara’s Wheel,” she mumbled mostly to herself. May cocked an eyebrow in her direction and Elsa nodded in response. She’d had a mild interest in perpetual motion since first introduced to the subject in seventh grade. She knew all about the classic machines and had even read about the new free energy theories at the website of Gerry Martin, an eccentric and outspoken proponent of the theories.

  A child prodigy, at the age of 13, Gerry Martin had built her first PMM. Now at 21 she had a whole congregation of believers around the world. Elsa read about it all, but didn’t understand much of it. It made for interesting thought experimentation, though. Like everyone else, she was skeptical and amused. She sat forward, interested in hearing Mr. Brown’s take.

  “This device is based on the design for the very first documented perpetual motion machine called Bhaskara’s Wheel. Bhaskara came from 8th century India. In the 12th, his wheel design was brought to the west where it sparked a search that goes on to this day for a machine that produces more work or energy than it consumes.”

  He turned from the wheel to the initiates who had remained standing on the far side of the contraption.

  “It is the task of our brand new members to explain why this wheel is not, in fact, a perpetual motion machine. And keep in mind that it’s not because of—”

  “It’s because of friction,” Cyndy Newman blurted out.

  “Friction.” Mr. Brown finished his sentence.

  Cyndy was a bright student. Tonight she was nattily dressed for the occasion in yellow crepe slacks and shirt and black indoor frock coat with a T-Wireless patch on the back side. Galileo’s hat was jauntily cocked to one side and she’d pulled a glob of her Clairol Nice ‘n Easy red hair to the opposite side of her head, setting the hat off nicely. Despite her sharply accessorized appearance, Mr. Brown frowned at her.

  The students in the seats laughed. Mr. Brown acknowledged this with a quick glance.

  Elsa shook her head sadly. She had always thought the same thing about friction, but having studied on her own, she knew a bit more about it than Cyndy Newman and probably everyone else here with the exception of Mr. Brown. Wasn’t really Cyndy’s fault that she didn’t have the knowledge she needed to avoid embarrassing herself.

  Mr. Brown continued. “Everyone assumes that very thing. Certainly friction would be a problem for the machine, but with bearings and grease, we can overcome friction for the most part. Enough to have a more efficient machine at any rate. Nope, not friction. The problem lies with the laws of physics. They prevent Mr. Bhaskara’s wheel from turning perpetually without extra input of energy. Ms. Newman, since you’ve volunteered to begin . . . ”

  The class laughed. Mr. Brown acknowledged it with a knowing smile and head bob.

  “Tell us first why the inventor believed this would work perpetually.”

  Ms. Newman’s face reddened, matching her hair. She faltered. She scratched her chin and laughed a little and then caught her breath. She hadn’t expected the spotlight so quickly. She’d reacted subconsciously when she blurted out the word “friction,” and now she was sorry.

  “Well,” she started and then sniffed back a bit of air through her nose, a play for time. She adjusted her beret to a less jaunty angle. “Four of these things up here . . . ”

  “Lead weights,” Mr. Brown assisted her.

  “ . . . lead weights are on the right side and three are on the left, and one is hanging in the middle so, um, so the wheel will go this way.”

  She stepped forward to push the erector wheel to the right. For a moment it looked as if it was indeed going to go forever, but only for a moment. It soon wound down.

  “And then it stops,” said Mr. Brown.

  “Well, if there wasn’t any . . . ” Ms. Newman cut herself short.

  “Any what?”

  “Um.”

  “I know you weren’t going to say ‘friction,’ were you?”

  “Um, no.”

  Stifled guffaws from the audience.

  Mr. Brown turned to the students. “Tha
t’s the problem with these darn demonstrations, there’s always so much inconvenient friction to overcome. Unfortunately, the friction is in your brain.”

  Full out laughter.

  “The friction is from your resistance to see that friction is only a minor problem. As I said, with bearings and a lot of grease you can almost eliminate friction. So when this is spinning and four lead weights find themselves on the right side, three are on the left, and one is dangling in the middle neither right nor left, why will the wheel not continue to turn? At any one point in time there’s more weight on the right side. Always, yes?”

  The students bobbled their heads in baffled assertion. Elsa sat riveted. She knew the answer, could see it there plain as day. She had an urge to call it out but she was not an initiate and it was not her night and she was terribly, terribly inhibited. And Mr. Brown was terribly, terribly annoying dragging it out like this. He was such a show-off.

  “Mr. Davidson,” Mr. Brown called on the pudgy boy standing next to Ms. Newman. He wore a Sony scheduler on his wrist and cowered visibly when he heard his name. “Why is the wheel fighting gravity? Why does it not do what everyone can see it can and surely must do?”

  “Uh . . . ” Mr. Davidson paused to clear his throat. “There is a pull of gravity in the opposite direction of each lead weight. Added all together, they pull in both directions equally on each thing . . . ”

  “Lead weight. Terrific answer. Great answer. Wonderful answer.” Mr. Brown turned to the crowd. “And wrong, of course.”

  The class laughed. Elsa rolled her eyes.

  Mr. Brown signaled everyone to quiet down. “Gravity does pull against the weights as they rise, but there’s more lead weight on the right side as Ms. Newman so ingeniously pointed out. The wheel is constantly overbalanced. It should move to the right. And in fact . . . ” He gave the wheel a slow turn. “ . . . as you can see by turning it slowly, there’s actually more weight on the side pulling it in the opposite direction. But that weight is there only for a moment and what really happens . . . ”

  He continued turning until the lead weight at the top of the wheel suddenly jerked forward to the right as its arm unfolded.

  “ . . . is that the position of the top weight changes drastically and forcefully. It swings out away from the center of rotation. Why isn’t this minute amount of forward acceleration enough to keep the thing going perpetually? Mr. Sun?”

  “Torque?” Mr. Sun blinked his answer which sounded more like a faltering question.

  “Uh, torque.” Mr. Brown frowned. “Good answer but not totally right. Torque is what is giving it that bit of energy actually. Since torque increases the further you are from the axis of rotation, it gives it that little extra push when the arm extends out. This should be enough to make it perpetually move to the right, so that’s obviously not what’s stopping it. Yes!”

  He turned abruptly to the audience like a maniacal lawyer proving beyond the shadow of a doubt that Miss Scarlet couldn’t be in the conservatory with a wrench because he has the card that says she was in the laundry room. The audience nodded their heads. Mr. Sun looked at his feet. He didn’t know why torque was not totally right. He did not really know what torque was. It just sounded so right.

  Mr. Brown turned back to the row of initiates. “How about it, Ms. Danforth? If it’s not torque stopping this crazy thing, what is it?” He took a step with an outstretched hand to the lanky chestnut-headed one in the center of the line of students. Her face was hidden by hair hanging straight down in front of her face.

  The class fell silent. Ms. Danforth was painfully shy. Surely, Mr. Brown would not rank out on her. It would be too hurtful to watch.

  Elsa wished she could disappear. She hated when Brown went off on students. It was bad enough he won points at stupid kids’ expense. It was bad enough when he used Elsa as an example of what a good student was. But this badgering of someone crippled by shyness was the worst. Sure, Julie Danforth should grow up and get a grip, but Brown was not a child psychiatrist. He wasn’t even a real teacher. It wasn’t his place to force someone to be something they weren’t.

  Ms. Danforth hooked the left side of her mane behind her ear, took a deep breath, and with a hopeful questioning look on her face mumbled something.

  “What?” Mr. Brown cupped his ear in his hand and stepped to just in front of Ms. Danforth. “I didn’t hear you,” he said.

  She whispered something into his cupped hand.

  The man stepped back to regard the audience and bark: “Ms. Danforth, can you please say that louder for those of us in the cheap seats?”

  The class snickered.

  Elsa racked her brain for a way to help Julie Danforth.

  Meanwhile, Ms. Danforth, quite sure she’d made a blunder and didn’t know whether to run out of the room now or do as she was told, whispered, “Inertia?”

  “Inertia!” thundered Mr. Brown. “Inertia. Class, Ms. Danforth feels that inertia is what’s stopping the wheel? What shall we do with such an answer?”

  Regardless of their previous empathy toward Ms. Danforth, they could no longer hold out against Mr. Brown’s wit. They laughed while their teacher stood with his hands on his hips as though thinking about whipping the poor girl for her stupidity.

  Elsa could stand it no longer. It wasn’t so bad to tease Cyndy Newman or Gerald Davidson, but Julie Danforth? That was just macabre.

  “But she’s right,” Elsa said from the cheap seats.

  The crowd hushed immediately and turned to the back of the room. Their laughing faces turned into those of surprise and maybe awe. The initiates up front smirked at what they thought was someone finally putting Brown in his place.

  “Ah!” Mr. Brown said, leaping forward to shake the hand of the answerer. Elsa shrank back in her seat, annoyed that she had inserted herself into the drama.

  Mr. Brown pulled her to her feet. Elsa looked sheepishly at Mr. Brown. “I mean, rotational inertia, anyway.”

  “Yes! Yes!” Mr. Brown screamed. “Rotational inertia! The inertia of a rotating body. The measure of resistance of an object to changes in its rotation. It increases with the distance from the center as the something rotates. Think about a figure skater, kids. What happens when she does her Hamill Camel?”

  Mr. Brown ran to the front and assumed the pose of a figure skater mid-Hamill Camel. “She spins lazily with her leg sticking out and then when she leans down, reaches her hands to her feet, what happens?”

  Elsa sat down. Let someone else answer.

  Ms. Danforth mumbled up front. Mr. Sun spoke out loud. Mr. Davidson and Ms. Newman fairly shouted. The entire room of people, even May, said it: “She goes faster!”

  “Yes!” Mr. Brown jumped up and sang out. She goes faster!” With the class laughter egging him on, he spun around, positively giddy that a correct answer had been produced and the trial was almost over.

  Suddenly he came to a stop and whispered forcefully: “She goes faster.”

  He straightened. “When her extremities come in to the center of the spin she speeds up. The rotational inertia, in this case Dorothy Hamill, is greater when she is spread out, radiating out, so to say. But when she pulls in, her rotational inertia is smaller because the radii of all the little bits that make up her body are smaller. She speeds up.”

  He raced to his wheel contraption. “Although there is a momentary increase of torque on the side going down when the lead globs at the top slam over, the rotational inertia for that lead glob is at the same time greater because its distance from the center is greater.” Mr. Brown spun the contraption. “You’ve got torque and inertia fighting each other. The torque wants to speed it up and the inertia wants to slow it down. The thing stops moving.” The thing stopped moving.

  He picked up his Georgia Pacific pointing stick and indicated the lead weight sitting at the bottom of the wheel. At its resting place it had the greatest distance from the center.

  “Here we have the greatest torque because it’s farther away fro
m the center, but we also have the greatest rotational inertia to overcome to get it back up to the top. They cancel each other out. This pig won’t root!”

  Triumphantly he leaned his stick against the whiteboard, picked up a marker and scribbled “Q.E.D.” on the board.

  “Quadratic Equation Done,” one of the juniors said. Everyone including Mr. Brown laughed. Even Ms. Danforth the hero of the day, smiled a little. The normal color in her face had by now returned.

  Having come to the final conclusion so elegantly, the initiates became full-fledged members of the Northawken Science Society. They donned ceremonial robes and wore them for the rest of the evening over their ads for ibooks and Xplore. They drank a ceremonial Morton salt solution to symbolize the imbibing of scientific knowledge. The president gave each a Print•Write laminated card with the TSS (Twenty Standard Subroutines used in universal applications) and a list of the websites of the biggest software developers (as if any high school student didn’t have that already burned into their brains). Each member scheduled a day of tutoring freshmen in dead languages such as Fortran, Cobol, and Visual Basic. They signed a contract stating they would develop a personal computer game by graduation (as if they hadn’t already done that two or three times).

  After listening to the description of the initiation requirements, Elsa wondered about getting involved with the group. She had no desire to spend a weekend in the language lab. She had no desire to program. When Mr. Brown promised to demonstrate in vitro fertilization at the next meeting, she moved in a decidedly negative direction. She hated biology almost as much as she hated coding. And these people seemed so cruel. How could they let Mr. Brown go off on everybody like that? It’s not the kids’ fault if they don’t know what they haven’t been told. And did she really want to spend more time around Mr. Brown than she had to? Despite the action-packed demonstration on Bhaskara, the Science Society was obviously no place for her. She couldn’t imagine the real geniuses of the world, people like Gerry Martin, ever being found within a hundred miles of a science society. Why, then, would Elsa Webb? The tall, new boy wasn’t even there.

 

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