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12 March 2023

The Physics Adventures of Edna & Bertha - Episode 1

 


During the Pandemic, I did live AP Physics 1 exam prep shows on the College Board's Youtube channel.  Two audience members in particular maintained correspondence with me for a short time afterward: Liliana Gordan, and @aldescery.  The art above was drawn by @aldescery after I had joked in a show that there should be a spinoff called The Physics Adventures of Edna and Bertha.  She thought the idea had promise!  Then, Liliana arranged to zoom with me several times to help develop a plot outline for an "episode."  

Ideally, this would be an animated series based on @aldescery's artwork.  However, until a studio steps forward with a zillion dollar check, I'll stick with writing episodes as short stories.  

The episode below is based on the 2017 AP Physics 1 exam, problem 3.  Liliana came up with the framing device, including the human characters (other than Greg, of course!).  She wrote a first draft of the beginning.  I edited that, and wrote the rest.  

Hope you enjoy!


Emmy, Bri, and Andy lounged around the desks inside the physics classroom.  Their teacher was out making his lunch, but the trio stayed, scribbling notes to each other on scrap paper.  A debate was in progress.

“Look, can we take a break?” asked Andy.  “We’re talking in wider and wider circles.  I’m just gonna use mvr and be done with it.”  Emmy looked to the sky.

“OMG, Andy,” she said.  She actually said the letters, oh - em - gee.  “Your pet equation is just for a point object.  This is a rod!   How is a rod a point object?”

“I can point it at you, I can,” Andy said with a smile.  But he did pick up a meterstick and point it across the desks toward Emmy.  Emmy made a soft bear growl.

They both looked at Bri, who had been quiet for a while.  Emmy pled her case. “Come on, Bri, what do you think?  Shouldn’t we be using L = Iw for the rod’s angular momentum?”

Andy’s rebuttal: “Not only is Emmy using the wrong equation, she even wrote a doubleyou rather than an omega.  Look at the pointy bits!  It’s not “eye omega”, it’s mvr, I know it.”

Bri didn’t respond right away.  To her relief, the classroom door opened right then, cutting off Emmy’s forthcoming riposte.  The three physics students saw a determined little girl enter.  She had big brown eyes, a  blue and yellow floral, frilled skirt, two big buns, and a bright smile. She carried a worn, knitted green cloth grocery bag on her shoulder—something seemed to click inside it. She looked over at the group, beamed with a wide grin, and sprinted across the room to grab a chair at their table. 

She sat down.  “Hi!”

“Hi,” all three students said, laughing nervously. 

An awkward silence followed. Emmy, Bri, and Andy stared at each other.

‘Who is this kid?’ ‘Don’t look at me.’

The little girl broke the tension. She pointed at the paper on the table. “What’s that?”

“Our homework.” said Emmy. 

The girl giggled. “It looks really cool.”

“Thanks.”  Emmy continued to talk to the little girl, with Andy joining in. Both politely fished for clues. The girl’s answers seemed purposefully vague. Is she lost? No. Is she a teacher’s kid? Not exactly. 

Emmy and Andy became ever more unsure, the little girl ever more amused. 

Bri remained silent, observing the three jars in the little girl’s green bag: One seemed like a store-bought jar of pickled jalapeno peppers; the second, like a homemade jar of canned pickles; and the third, like it was half full of jelly beans. Bri looked at the girl with a distant familiarity. Then she remembered.

“Oooh!” Bri palmed her forehead. “Aren’t you Mr. Jacobs’ niece?”

“Yep,” she smiled

.“Yeah I remember him mentioning you and your collection.”

“Oh right!”  said Emmy. “Why didn’t I think of that? You’re the homeschool girl he’s always talking about.”

“Why didn’t you tell us that?” asked Anthony.

“I wanted it to be a game!”  The little girl giggled.

“What’s your name?” asked Bri. 

“Charley.” 

***

“My school is over today, but I get to come to physics class with the high schoolers!  I love physics, just like Greg does!  Nice to meet you Bri!  And who are you?”

“I’m Emmy, and this” —she gave an only sorta-playful punch— “is Andy.  Who were you talking to there?”

“This is my pet hippopotamus Edna.  Say hi to Edna!”

Emmy saw Charley remove what looked like three glass jars. She lovingly placed them on her desk as she talked softly to them.  Emmy saw that the two pickle jars had bows on the lids, one pink, one blue; and that the jelly bean jar was on its side.

“Hi, Edna,” said Emmy.

“And this is Bertha, who is a very nice elephant, and this is Anthony.  Edna says he’s a mean hippopotamus.”

“And why does she say that?”  asked Emmy.

Andy couldn’t hold his tongue any longer. “Because he’s a jar of jelly beans?”  Everyone looked at him.  Charley growled.  

“He’s a HIPPOPOTAMUS.  Not everyone can look beautiful like Edna and Bertha do.”

“But…” Bri glared at Andy, and Emmy punched his arm again, just a little bit too hard. “Okay, okay, I like your hippos, Charley.”

“And Bertha!  She’s an elephant, and she’s very smart.”

The bell rang for the start of class.

***

“Hi, all!  So, here’s the question you did for today.  In part (a), we’re asked where to hit the bar to produce more rotational speed—left or right of point C?”

“Left of point C, near the pivot!” says Andy.  “The pivot is the key spot! Hit it there!”

“Huh, said Charley softly, but not so softly that the other students couldn’t hear her. That’s what Anthony said!”  Other students laughed hesitantly at the idea of Anthony speaking.”

Emmy spoke up.  “But to apply more torque, you’d want a longer lever arm, so farther from the pivot!”  She sighed, and glared at Andy.

“Emmy’s right,” Bri said.  “We can also think of angular momentum conservation.  The angular momentum of the disk is mvr because it’s a point object, and that angular momentum is Iw of the rod/disk after collision.  To get a large omega, we need a big r—and r represents the distance from the pivot at collision.”

“Yeah, Bertha agrees with you, Bri! And she’s the best of my friends at physics.”

“You mean the best jar of pickles?”  Andy asked.  He wasn’t particularly happy about being disagreed with.

“Bertha is NOT a pickle!  She’s the best elephant in the world!  You be nice to her, Andy, or Edna will charge at you.  Hippopotamuseses are the most dangerous animals in the world when they’re angry.”

“Shut UP, Andy”, said Emmy.  “Be nice to the little girl and her pets.”

Charley turned her back to Andy as the bell rang to end class.

***

“Guys.  Pirate Larry is causing trouble again.  He’s trying to shut down the school.”  Bertha’s face seemed grayer than usual.  

“So?”  said Anthony.  “We get a day off of school.  I could use a break.”  

“Thinking of yourself as usual, eh, Anthony?  What about us?  What about Charley?!?  If Pirate Larry manages to shut the school down, she will be so lonely… she loves us, but she needs human friends, too.  Oy, Anthony, sometimes you are such a mean hippopotamus.”  Edna was not happy.

“But…” Anthony realized the truth of what Edna said.  “Humph.” he said.  Anthony folded his arms and sat quietly to listen to the rest of Bertha’s report.

“This time, he has a homemade snow machine.  He’s trying to dump a meter or more of snow on the Superintendent’s house so that school will be called off tomorrow!”

“Well, that’s easy enough to foil,” Edna said.  “I’m headed to Larry’s Lair to shut the stupid snow machine off.”  

“Yeah, sure, easy as that, right,” said Anthony.  How do you even know where Larry’s Lair might be?”

“Anthony, you know how hippopotomusses who aren’t lazy go on safari regularly?  See, there’s a watering hole in the abandoned rock quarry just out of town.  I saw Larry’s Lair’s lights one night, when he thought he was all alone.  Come on, we’ve got to get there while there’s still time.”

“Ooh, calling me lazy, eh?  I happen to be ready for action at any time!”  He pulled out a mask, plastic sword, and makeshift rubber helmet from his toy drawer. “Engarde! Il y a un poisson dans votre bibliothèque!”   

Edna rolled her eyes theatrically.  “You look like a bowling ball,” she told Anthony.  Come on, Bertha, at least I’m taking this threat seriously.  Let’s go stop the snow.  She headed east.  Bertha followed immediately.  Anthony looked around, realized they weren’t kidding about heading into danger; and that Charley was sound asleep, oblivious of the ungulates’ presence or absence.  So he, rubber helmet and all, rolled into action as well.  “Wait up!  I’m coming with!”

*** 

Pirate Larry’s plans were opaque to most people.  His lair was built into the highest layers of the quarry’s rock wall, visible only from the watering hole at the quarry’s bottom. 

Edna snuck nearer and nearer to the quarry.  Contrary to what many folks think, hippopotamuses can move quite stealthily.  She looked over the edge.

There he was.  Pirate Larry, the monster who had one day caused every fire alarm in the school to sound 30 seconds after anyone entered the stalls in the second floor bathroom in the science wing.  Who set the school bells in each classroom off by just the right amount such that the end of fifth period happened in a longitudinal wave that propagated across the school for 12 minutes.  Who had created a Ceiling Roomba to sweep Mrs. Smith’s room, raining down all 236 pencils that had been stuck there by Joey Jackson and his bored friends in the back row.

“He looks like a big onion. He can’t even walk! He hops around!”  Anthony was shushed by Edna.  More quietly, he asked, “How do you know he’s a pirate?  It’s not like he’s wearing an eyepatch or anything.”  

Bertha said, “You know how some people call you a jellybean?”

“Some people who are very wrong call me a whole jar of jellybeans!”

“Well, it’s the same for Pirate Larry.  Some people who are very wrong think he’s a harmless Vidalia Onion who can’t move or talk.  And that’s how he gets away with so much mischief.  People underestimate him.  Like they do us.”

“Shhh, Bertha!  He’s coming!”  

***

“Huh-HA!” shouted Larry. He stood at the entrance to a makeshift shed, inside which was a contraption.   “It’s ready, CrabbyCrabbyCrabbyCrabby!  See, the fancy ski resort up the mountain uses bespoke-engineered snow guns that fire high pressure water and air, properly designed for safety and functionality, making the snowmaking experience simple, wet, and white.

But sometimes, CrabbyCrabbyCrabby, sometimes, I wake up in a disused landfill, collect a decrepit box fan and a moldy fridge, hotwire ‘em both to a leaky methane-fueled generator, and create the budget ski lodge smelly localized snow storm that will… SHUT DOWN THE SCHOOL!  Huh-HA!

“Who the heck is he talking to?” whispered Anthony.  Bertha didn’t speak, she just pointed with her trunk.  Next to the onion-shaped pirate sat a horseshoe crab.  Or perhaps just a horseshoe crab skeleton?  It was hard to tell from this distance.  It must be a skeleton, right, because Larry’s Lair was hundreds of miles from the nearest saltwater.

With a huge, strong, onion-shaped muscle, Pirate Larry shoved the door to the shed.  It flew around its pivot, the generator hummed to life, and a cloud of snow shot out of the gun.  Way up in the air it fountained, toward a mansion several hundred yards from the quarry.  

“That’s the Superintendent's house!” Bertha said.  “Look, there’s already a few centimeters of snow on the lawn!  Oh, no.  This really is going to shut down the school!”

Larry picked up the crab, or its skeleton, and walked deeper into his lair.  “Let’s go get a soda, CrabbyCrabbyCrabbyCrabbyCrabby.  My plan has decommenced.  Or, commencated.  It’s underway, anyway.”

“I thought he had discovered us when he shoved the door,” Edna said quietly.  “Phew.  My heart can go back to normal hippopotamus frequency now.”

“I thought you like thrills, Edna,” Anthony said. “You’re always the daredevil who rides the physics demonstrations!”

“Yeah, but I trust that physics demonstrations work, because I understand the rules of physics.  Pirate Larry doesn’t have any rules.  Come on.”  Edna carefully sidled up to a shed door.  When she was sure Larry was nowhere near, she beckoned the others to join her.

“Look here, Bertha!  There’s a big photogate above the door—it gives an instantaneous speed readout on that screen.  Bertha waddled over to inspect the screen.

“Yup, and there’s the trigger speed—that big heavy door has to go 88 cm/s or faster through the photogate to turn the generator on or off.  Think we can do that?”

“Of course we can,” said Anthony.  Just shove the door near the pivot.  Easy.  Watch me!”  He did shove, the door did move… moved 13 cm/s.  “Oh.  That door is heavier than it looks.

Back came the door to its original spot.  “Time to try again,” said Edna, “but this time let’s be smart about the physics.  Larry can provide a lot of torque on the door about the pivot, because he’s so strong he can apply a large force.  We’re not as strong as Larry, but we can apply a force with a large lever arm!  That should make some serious torque!”  Edna pushed at the edge farthest from the pivot—still only 40 cm/s.  “Hrrummm,” said Edna, which is a fierce hippopotomus curse.

“Okay, I’m getting desperate.  If I run at the door instead of just shoving, then my angular momentum about the pivot will transfer to the door— that should make the door go faster!”

“Edna, what are you gonna do, run in circles?  Pshaw.  If you’re running in a straight line, you won’t have any angular momentum at all to cause a change in rotational speed.  Phthph.”  Anthony always was so sure of himself.

Edna opened her mouth to categorize this latest Anthony comment on the Mean Hippopotamus scale, but Bertha jumped in to keep the peace—and to keep the argument from escalating when they needed to be very, very quiet.  “Anthony, Edna’s right—a point object moving in a straight line has angular momentum mvr, with r the closest distance from the pivot.  Her idea could work.  Let her try it, and be quiet whether it works or not, okay?  We do NOT want to be captured by Larry.”  Even the brave and noble elephant shuddered visibly at the thought.

And so, Edna took a running start, grabbed the door at the far edge, swung through the gate… and only got 62 cm/s.  Edna’s eyes seemed a bit moist to the others as she let go and sat on the dirty ground, staring despondently at that glowing screen.

That’s when Edna saw the equation.  “Bertha!” she hissed.  Look at this!  I think this is an equation for the speed of the door as a function of other stuff!”

“What other stuff?” Bertha asked.  Into the room she came, instructing Anthony to stay outside on lookout.  “Make animal noises if something happens.  I need to see this equation.”

Bertha saw.  “Hey, the mass of the object colliding with the door is in the numerator.  That means, the heavier the colliding object, the faster the door will move.  I’m much more massive than you!  I’ll run at the door.”

“But Bertha, you know you don’t like riding things… look, I can put some rocks in my pockets. A few hundred ought to do it.  I’ll make it work.”

“Edna, it’s gotta be done.  Stand away from the door.  I’ve got this.”  And so the very large elephant dipped her blue bow low… and charged at the door.

Bertha leaped, grabbed onto the door, swung through with a great but inadvertent trumpeting… and the door did indeed move faster through the photogate.  Up to 75 cm/s.  

Not enough.

And now Bertha sat swaying on the dirt.  She couldn’t quite focus her eyes, but her brain kept a very focused focus on the serious nausea messages coming from her tummy.  Oh, oh, oh.  The other ungulates knew from long experience how susceptible Bertha was to motion sickness.  Elephant upchuck was possible at any moment now.  And the snow piled ever higher around the Superintendent’s house.

Edna and Anthony began to make whatever sounds they thought the local fauna made (“Hoot, hoot?  Nah, no owls, not enough trees.  “Wiggle wiggle?” “What animal makes that sound?”  “There are worms around here, I’ve seen them.” “And they say ‘wiggle’?  Oy.”)  around the quarry, frantically trying to alert Bertha to the incoming danger.  But if she heard, she could not physically act.  She sat there, now gray-green in the face, while her nemesis hopped inexorably from the soda room.

Pirate Larry stood before Bertha the Elephant.  His beady onion eyes seemed to bore into Bertha’s very elephant soul.  Bertha tried to stare back, but her eyes rolled.  She covered her mouth with her trunk, and stared instead at the dirty floor.

Pirate Larry taunted Bertha.  “Ah, Bertha.  Who entered my lair uninvited and unwanted.  Please do not remagurgitate—reguglitate—barf on my floor.  Pickle juice is so, so difficult to clean up.  Huh-HA!  But you’ll be doing the cleaning up, because you are in my clutches, Bertha who is nothing but a jar of pickled pickles.  

“You amost upset my grand plan, oh Bread and Buttered One.  Yes, you managed to figure out how my special snowing machine works, but you did not figure out how to stop it!  Oh, you might be good at physics, but what good is “good at physics” if you can’t prevent my insidiousness from insidiousing? 

"And now, you are helpless as the snow approaches three feet deep.  Huh-HA, Bertha the physics “elephant”, three feet, not a meter, because I use outdated units based on the size of a king’s foot.  And you don’t even have a feet, you have hooves!  Huh-HA!  Perhaps I should make the snow twenty elephant-ears deep!  

"My jury-rigged snow machine is WORKING!  Huh-HA!  I’m ready to turn it up, and to bury the Superintendent’s house. Yes, I’m ready!!  But first, I will taunt you a second time.

Edna broke down in tears.  All her, and Bertha’s, bravery had been for naught.  Poor Bertha!  Pirate Larry might do anything to her, once he ceased his obsession with the snow machine.  But Edna could do nothing.  She couldn’t make the door go any faster!  And she couldn’t figure out how to rescue her friend.  

Meanwhile, Anthony took stock of himself.  He heard Pirate Larry begin his second taunting.  He saw Edna’s hippopotamus tears.  He saw that he looked like a baby hippo in a Halloween costume, a costume so silly that the baby hippo himself must have made it.  The rubber helmet looked ever more ridiculous as the gravity of the situation caught up with Anthony.  He hadn’t been taking this adventure seriously at all.  And now his elephant friend was seriously in trouble.  

Anthony got mad.

With a Hrrummmm! so loud that even CrabbyCrabbyCrabby seemed to turn his head toward the sound, Anthony charged at the door.  His arms flailed wildly as he reared up in a final leap.  

But Anthony’s wavy wavy arms couldn’t grasp the door.  His body twisted midair, so in the event it was Anthony’s silly rubber helmet that hit the door, well, head-on.  

Anthony bounced backward, nearly as fast as he had been running.

The door swung.  Noticeably faster than even Bertha had managed.  The photogate triggered - 120 cm/s, it read.  The snow machine creaked, shook, and stopped.

The door kept swinging, though, by Newton’s first law for rotation.  It bopped hard into the onion tuchus of Pirate Larry as, mid-taunt, he stood over the retching Bertha.  Larry spun around involuntarily, rotating nearly 18 radians in barely a second before collapsing.  Now there were two sick beings on the floor of the lair.

While Anthony picked his stunned self off the floor, Edna alone kept her wits.  She raced through the door before it could reset.  Out came the emergency motion sickness tablets, which Edna always brought when she was with Bertha, the same way some folks carry epipens.  Bertha gratefully, but not gracefully, hauled herself off the dirt floor and staggered toward the lair’s entrance.  

A moment later Edna was supporting an elephant under one leg, and a mean but groggily heroic hippopotamus under the other, as the three ungulates swayed and lurched away from the quarry.

“Arrrrrrrrrrrrrrrrrrrrrrrrrrrrr!” came the sickly piratey moan of frustration from Larry’s Lair.

***

Edna helped Bertha lean against Charley’s bed, where Bertha fell asleep instantly.  Edna gently led Anthony to his full if slightly stagnant bathtub, where he took off his equipment and got in.  (Like all hippopotamuses, Anthony preferred to sleep underwater.)

Edna tried to stay on watch for a bit.  But she soon gave up and got into her own rather more sanitary sleeping pool.

***

“Good morning, Edna, who is a very nice hippopotamus!”  Charley helped Edna dry off, and then re-tied Edna’s pretty pink bow.  “You look like you had quite a night—your bow was very ruffled!  Please wake up Bertha and Anthony while I get dressed to go to school with Greg!”

Bertha was already up and about.  “Edna, what are we going to tell Charley!  She’s going to be so disappointed when she sees the weather report.  And the school closings.  Anthony’s brave charge may have stopped the snow and briefly stunned that terrible onion being, but all Pirate Larry had to do was trigger the photogate again.  He’s had time to put meters of snow on the Superintendent's house by now.  That’s impossible to dig out of!  Even if there’s no other snow in the city, the superintendent will close the school, cause she won’t be able even to see beyond her house!

“I don’t think the snow is as deep as you think,” Edna said.  

“Look, there’s the superintendent on television.  I wonder why they’re interviewing her?”

“You had told us school would be closed today.  Why did you change to only an hour delay?” asked the reporter. 

“What a weird night.  First the snow—smelly, brownish-white snow—piled up past my first-floor windows.  Then all of a sudden, it stopped snowing… and, well… I’ve never seen such a thing happen before.  I don’t know that I can even describe it.”

Edna turned off the television quickly, before the reporter could ask a follow-up question.  “Let’s not worry Charley.  School’s happening today.”  

“Edna, what aren’t you telling us?” Edna had moved just a bit too quickly, and Bertha the perceptive elephant noticed.

“Do you guys remember when both of you and Pirate Larry were all sitting stunned on the floor?  Well, before I rescued you, I may have blocked one of the photogate beams with CrabbyCrabbyCrabby’s carapace.”

“Oh!  Wow!  Great work, Edna!”

“Wait, what?  Why is that great work?  Are you trying to steal my lightning, Edna?  I’m the one who stopped the snow, remember!”  Anthony stuck out his chest proudly.

“Oh, Anthony, you are such a mean hippopotamus!  Don’t you see?  When Pirate Larry tried to start the machine again, the door only triggered the first photogate beam, after CrabbyCrabbyCrabby had already triggered the second one.  So the beams were blocked in reverse order!  Larry’s snow maker reversed its angular velocity, and vacuumed all the snow back off of the Superintendent’s house!  I imagine that Pirate Larry wailed rather intensely when he saw.”

Bertha and Anthony stared at Edna.  Edna thought they would stare right through her.  Which in fact they did—their eyes focused on Charley, who had entered the room behind Edna a moment earlier. 

“School’s on an hour delay.  That’s sad, but I get to go to Greg’s class eventually!  What are we not worrying me about, friends?  And who is Pirate Larry?  I do do do want to know!”

The ungulates looked at one another.  “Well, Charley, it’s a long story,” Bertha said.  “But I guess we have an hour to tell it now.”

***

Ding went the bell, and twenty students enthusiastically piled into the physics classroom. Bri, Emmy, and Andy headed to their seats, which were all together in the back of the room.  

“Charley!” called Emmy.  “Come sit with us!”

“Hi, Emmy!” The little girl gave Emmy a high-five, or at least the highest-five she could pull off at age 6.  “I’m so glad to see you!  We almost didn’t have school today—we foiled Pirate Larry’s snow, we did!  Hemph!  Well, by we, I mean they.”  Charley gestured to her three friends, that still looked for all the world to the teenagers like glass jars.  Though two of them had bows on their caps.

“Oh, your hippos?” said Andy.  “What did they do?”

“And Bertha, too, who is a very nice elephant.”

“Remember the problem Greg gave you yesterday?  It was just like that!!”  Charley was so excited she nearly jumped into the air.  She pointed to the diagram on the students’ paper.  “Anthony pushed the wrong side of point C, so he was unhelpful.  Edna says he’s a mean hippopotamus.  Edna and Bertha were so brave!  They transferred their angular momentum to the rod, but that wasn’t enough.  Bertha’s mass was in the numerator, so she almost made the rod go fast enough.”

“Bertha had the best plan.  But Pirate Larry captured her!  It was scary.  Then Anthony… he got so mad, he bounced back off the rod.  And the rod went fast enough to open!  The snow stopped, and everyone was saved!”

Bri and Emmy looked at each other.  “That’s a good story, Charley.” Bri said.  

“Not just a story! They were there!  It happened! 

Bri figured it out: “Of course!  Edna and Bertha gave the door all of their angular momentum.  But Anthony… not only was he running faster for more initial angular momentum; he BOUNCED OFF in the other direction!  So Anthony changed his momentum almost twice as much as Edna or Bertha did, meaning the door changed its momentum by much more and went really fast!”

Anthony saved the day with physics even if he didn’t quite know why.

“Maybe next time Anthony could trade his jelly beans for jumping beans, and he could bounce even faster,” Andy laughed, looking straight at Anthony.  “Don’t see where he’d put a rubber helmet if he had one.  Maybe he had 40 helmets, one for each jelly bean?”

Charley hung her head, and stifled a brief sob.  “He’s a hippopotamus.  It’s not his fault he’s not beautiful like Edna,” she said with quiet sadness.

“Okay, here’s the quiz,” Greg said.  Charley buried her head in her hands while the students worked.

In contrast to Charley’s demeanor, Bri, Emmy, and even Andy perked up immediately.  The last question on the quiz was familiar!

In case 1, the disk sticks to the rod.  In case 2, the disk bounces backward off of the rod.  In which case does the rod move with greater angular speed after collision?

The quiz question was exactly what Anthony had done! They all understood the problem as well as any physics problem they’d seen all year.

***

“Hey,” Andy said after the quiz.  “Sorry, Charley, that I called Anthony a jelly bean.  He really helped us out, and I appreciate it.”  

Charley’s face was still fierce.  “That’s all very friendly, Andy, but don’t apologize to me—talk to Anthony!  He is a hippopotamus with feelings, even if Edna thinks he is mean.”  She stared at Andy.  

Andy visibly balked.  He knew he shouldn’t have insulted Charley’s “pet” to Charley’s face, but, still.  Could he bring himself to talk directly to a jar of jelly beans?  Especially right In front of Bri and Emmy?  There was sorta no way out.  Okay, so we’re doing this.

Andy set in his mind that that jar of jelly beans was a friendly guy just like him.  “Yo, Anthony!” he said.  “Thanks for helping us out.  You saved our bacon on the quiz.  Great job, man.  I appreciate it.  And you’re a fine looking hippopotamus.”

Charley beamed.  “Yeah!” she said to the three high schoolers.  “He really is a fine hippopotamus!  Thanks for noticing!  Although Edna is a bit miffed that Anthony got the credit.  He just got lucky, Edna says.  Edna knew the physics!  She says he’s a mean hippopotamus.”

“He’s not mean, Edna,” Andy said, “Just a bit slow on the uptake sometimes.  See you ALL—” Andy’s expansive gesture took in Bri, Emmy, Charley, and especially Charley’s animal friends “—tomorrow in class.  Can’t wait.”

As the students went out the door, Charley listened to the continued banter among the ungulates.  “But he is a mean hippopotamus,” Edna was explaining.  “Bertha was actually captured by Larry!  She was so brave.  I could have changed my momentum by twice as much if I had thought of it, too!  And I would have known why!  And yet, it’s Anthony who gets the thanks?”  Bertha just shrugged.

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