## Wednesday, May 22, 2013

### Special Guest: Jim Ottaviani

Today's special guest is author Jim Ottaviani. Jim has written several excellent comic books on science history including Dignifying Science: Stories About Women Scientists, Feynman, and Primates: The Fearless Science of Jane Goodall, Dian Fossey, and BirutÃ© Galdikas. Jim writes:

I live close to Detroit so I always have to hear about horsepower this, horsepower that. I prefer dinosaurs, though, so my question is this: How many Dryptosauruspower is under the hood of a beautiful, split-windowed, 1963 Corvette Sting Ray Coupe?

The whole point of "units" is to provide a convenient means of comparing quantities. Despite most scientists' insistence that the United States convert to metric units, there's nothing fundamentally special about meters and kilograms. You're perfectly welcome to continue measuring distance with a dead king's foot provided you don't mind remembering more complicated unit conversions. Still, perhaps it's better to have units we can all relate to. With that in mind, Mr. Ottaviani's question is a particularly useful one because the term horsepower is, at least for those of us in urban areas, a bit of an anachronism.1 According to Wikipedia,
The development of the steam engine provided a reason to compare the output of horses with that of the engines that could replace them. In 1702, Thomas Savery wrote in The Miner's Friend: "So that an engine which will raise as much water as two horses, working together at one time in such a work, can do, and for which there must be constantly kept ten or twelve horses for doing the same. Then I say, such an engine may be made large enough to do the work required in employing eight, ten, fifteen, or twenty horses to be constantly maintained and kept for doing such a work…"
In context, horsepower is a perfectly legitimate unit. If today an infomercial claims you'll lose weight three times faster with Bowflex than with a Shake Weight, than you could define

1 bowflex = 3 shake weights,

and in 100 years "shake weight" will be a legitimate unit of measure, not an utterly ridiculous punchline.

 The Shake Weight: laughing stock of the exercise community

Much like with the shake weight, we could easily standardize dryptosauruspower as a unit provided we can find the correct conversion factor between it and horsepower. A dryptosaurus is thought to have weighed about 1.5 metric tons or roughly 3.3 times the mass of a horse. This would put it closer to the weight of a giraffe or hippopotamus. Giraffes eat about 75 pounds (34 kilograms) of food per day, while a hippo eats about 88 pounds (40 kilograms) of food per day. Since a dryptosaurus is about the same size, it likely eats about the same amount of food.2 Let's assume the typical dryptosaurus takes in about 80 pounds of food each day.

 It's bigger than you, so it eats a lot more.

A 1000 pound horse takes in about 30 pounds of food per day, roughly 2.7 times less than the dryptosaurus. Food is a source of energy. Power is the amount of energy used in a given amount of time. Since power is proportional to energy which is proportional to the amount of food, it should be true that the dryptosaurus is roughly 2.7 times more powerful than a horse.3 We could use the following equation to convert from horsepower to dryptosauruspower:

1 dryptosauruspower  = 2.7 horsepower

 A 1963 Corvette Sting Ray Coupe with 100-dryptosauruspower

Depending on what kind of engine is installed in your Corvette, you could have a variety of different horsepowers. According to Wikipedia, typical values range from 250- to 340-horsepower. Using our conversion equation above, the horsepower of a 1963 Sting Ray Corvette ranges from 93- to 130-dryptosauruspower.

Thanks for a great question, Jim! You can find out more about Jim Ottaviani and his books at G. T. Labs or on Twitter.

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

[1] There are those who might ask why we would want to convert to dryptosaurus power since the dryptosaurus, having lived over 60 million years ago, is an even greater anachronism than the horse. A fair point, Dear Reader, to which I have two responses. (1) Dinosaurs are awesome, and (2) horses suck.
[2] I am, of course, making a big assumption here by assuming food intake is related to body size. The difference between dryptosaurus and a giraffe could be substantial given that one is a carnivorous reptile and the other is a vegetarian mammal. Even within one species, you can have a pretty wide range of values for caloric intake. For example, I'm pretty sure I eat about twice as many calories each day as my wife does. That said, the caloric need for similarly-sized animals should be roughly the same to within an order of magnitude. We can see this by comparing the giraffe and hippo, two very different but similarly-massed creatures that take in roughly the same amount of food each day.
[3] Here, we're talking about the average power output as opposed to the peak power output, which is theoretically what we're quantifying when we talk about horsepower. These could be somewhat different, but I suspect they're still relatively close.

## Friday, May 17, 2013

### Star Trek Review and Estimation

There's not too much I'll be able to add to what other people have already said more eloquently, but I'm going to put in my two cents in anyway. I just saw Star Trek: Into Darkness, and I have to admit I was disappointed. It wasn't Catwoman bad or even Phantom Menace bad, but it was quite possibly "Phantom Menace minus the scenes with Jar Jar" bad.

Don't get me wrong, Benedict Cumberbatch was pretty good as Khan1, but I found the editing to be downright dreadful. In one scene, Spock just barely pulls himself onto the edge of a flying car and in the next shot Khan kicks him back 15 feet from the middle of the car. Now, I could easily overlook one or two poorly edited shots, but I can't ignore the scene with Chekov holding up the much larger Kirk and Scottie, who are dangling over the side of a bridge. Mind you, Kirk couldn't hold Scottie by himself, but somehow the 130 pound Chekov has no problem lifting them both. I can only assume some amazing and dramatic miracle feat of strength occurred while the cameras were off, because a second later they're all happy and running through the Enterprise without any explanation. Whatever Chekov did must have been amazing to see, but apparently J.J. Abrams just wants us to fill in the details by ourselves (more on that in a moment).

While we're on the subject, when did J. J. Abrams decide to become Michael Bay?2 Seriously, I'd much rather see how that bridge thing got solved than watch another giant explosion that I'm just gonna tune out. And, no, Mr. Abrams, you can't just lazily copy highly emotional moments from the old movies and expect to elicit the same emotional response in your audience. Kirk's "death" didn't make me sad or even nostalgic. It made me think, "Hmm...they've got a cash cow of a franchise here and there's no way they're killing off Kirk, so I guess the dead tribble's coming back to life." That said, having Spock tear up did make me feel some genuine emotion, so I guess there's that.

Still, the main source of my disappointment has little to do with these small quibbles3 and more about the general direction this franchise has taken. The best part about old Star Trek is that it was actual science fiction, not cheesy action-adventure set in space. With that in mind, you can't just freeze a volcano and call it cold fusion without Gene Roddenbury and Isaac Asimov rolling over in their graves so fast we could use them as a renewable energy source.4  I'm used to Star Trek having a bigger message, and if there was one here I totally missed it.

Since this is Diary of Numbers, I can't justify ending this rant without at least some bit of calculation. With that in mind, my friend John had the best explanation I've heard for how Chekov could suddenly gain superhuman strength. According to John, "Russian Special Forces kettlebell workouts gives you strength of two men..."  Where would this put Chekov in the pantheon of great Russian weightlifters?

There's nothing the Muscleless Wonder and I take seriously if not for science and weightlifting, and this estimate combines both. If Chekov is as small as I think he is, he'd be in just about the lightest weight class of lifters. To get both Kirk and Scottie back on the bridge, I imagine him doing a motion similar to a snatch. I'd put Chris Pine and Simon Pegg at about 175 pounds each, meaning their combined weight would be 160 kilograms. With a 138-kilogram snatch, Halil Mutlu of Turkey holds the world record in the 56-kg division. Chekov would easily smash this record. Unless he's the next Pocket Hercules, there's no way he's pulling Kirk and Scottie back on the bridge.

Seriously, get it together, J.J. Abrams. I'm willing to give you a pass on this one under the assumption that you're distracted putting together a kick ass Star Wars movie. No second chances after that.5 Help me, J.J. Abrams.  You're my only hope.

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

[1] My buddy Matt was not so glowing in his endorsement of Cumberbatch: "I don't feel like I can call him 'Khan' because he isn't. He's British. And white. Khan Noonian Singh was of Indian descent. Hence the reason he took the title of Khan."
[2] QOTD from a friend on Facebook: "I'm pretty sure J.J. Abrams is the non-union Mexican equivalent of Christopher Nolan..."
[3] Let's call them "tribble quibbles"!
[4] Yes, I'm stealing that joke from somewhere, but I can't remember where, so I can't cite it.
[5] Though if I'm completely honest, I'm still probably going to spill out full price for whatever creatively emaciated junk they're going to throw at us. I can't help it....I need my cheesy movie fix.

### Father's Day Contest

Father's Day is in a month, and I know the perfect present for the sport-loving dad:

In fact, I'm holding a Father's Day contest. It's a little different than my usual contest. Normally, I give you guys a question to answer. This time, I want you to give me a question.  What's a good estimation question that every father would get a kick out of?

To enter, tweet your question to @aarontsantos by June 14, 2013. I promise not to spam your inbox or sell your email to evil corporate overlords. On the 14th, I'll select what I think is the most interesting question and answer it on the blog for Father's Day. The winner will receive a free signed copy of Ballparking to give to your dad (or anyone else you like).

***Edit*** Per popular request, I'm gonna say it's OK if you want to mail me your questions rather than tweet them. Send them to aaron at aaronsantos period com.

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

## Thursday, May 16, 2013

### Scientific Paper of the Week: Alpher, Bethe, Gamow

Oh, the things physicists do for a lark. Today's paper, titled "The Origin of Chemical Elements", describes how the Big Bang explains the relative abundance of hydrogen and helium in the universe.

 The universe expanding after the Big Bang.

While tremendously interesting in its own right, the content of the paper is not the reason for its selection. In my General Physics class, we just covered alpha, beta, and gamma decay. The authors of this week's paper are Ralph Alpher, Hans Bethe, and George Gamow.

"Well, that's a fun coincidence!" you say.

Well, not quite...

 Left to right: Ralph Alpher, George Gamow, and Hans Bethe, who's totally riding their coattails.

It turns out Bethe played no actual role in writing the paper. Gamow added him because he liked play on words with "alpha-beta-gamma". And they say physicists don't know how to have fun!

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

## Friday, May 10, 2013

### Special Guest: Derek Lackaff

Today's special guest is Elon University School of Communications Professor (and also my coolest1 brother-in-law) Derek Lackaff. Derek is working on a project called Better Alamance, which uses social media to help local residents share ideas on how to improve their community:

Derek wants to know...

How long would it take the citizens of Alamance County to put everything they know on the Better Alamance: Wiki, and how big would the wiki be when they were finished?

Great question, Derek! According to Wikipedia, Alamance County in North Carolina is home to roughly 150,000 residents. According to at least one source, a human brain has on the order of 2.5 petabytes of memory, which means 150,000 brains would have roughly 370 exabytes of memory. This data includes everything from which Alamance park needs the most improvements to what the final score was in the last Duke vs. Tar Heels game.

If a wiki page is anything like a text document, it would require anywhere from 10 to 100 kilobytes of memory.2 At this many bytes per page, we'd have about four quadrillion wiki pages of material stored in the mental matter of Alamance citizens. If we printed every page of the wiki, it would be long enough to reach to the Sun and back!

If you like the idea of using social media to help improve your community, let your voice be heard. Go here and vote for Better Alamance in the MacArthur Foundation-sponsered contest, Looking@Democracy.

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

[1] <cough> Caleb sucks <cough>3
[2] It could be substantially larger if contains large pictures.
[3] Just kidding.4
[4] No, I'm not.5
[5] No, just kidding again. I wuv u Cublub.

### Scientific Paper of the Week: Glowing Pickle

Have you ever tried to pass electric current through a pickle? "No...that sounds incredible stupid!" you say. But someone thought otherwise and discovered this:

 Homer Simpson: "Mmm...forbidden glowing pickle."

I first heard about this trick in Penn and Teller's How to Play with Your Food.  Penn and Teller heard of the trick through the Journal of Chemical Education.

 Fun Fact: Teller is actually normal height. He only looks short when standing next to the 6'6" Penn.

To brine a pickle, you put it in salt water. Salt contains sodium. When you pass electric current through the pickle, you excite the electrons inside the sodium. The atomic energy levels of sodium contain a unique doublet known as the sodium D line.

 "Atomic line spectra sure are purdy."

And thus we have our Scientific Paper of the Week:

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

## Thursday, May 9, 2013

### I Love My Students (Part 2)

Once again, I love my students.  We're covering Bohr's model of the atom this week.

 "The Bohr model: Sure, it's wrong and will give our students  conceptual difficulties later on, but let's teach it anyway!"  said every physics and chemistry teacher ever.

After class, one of my students sent me this:

There seems to be a strange periodicity associated with searches for the Bohr atom. I suspect most classes teach it at the same time every year, generally October or February.  Why am I teaching it in May?  I guess I'm just different.

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

## Wednesday, May 8, 2013

### Fire in a Bottle

Here's a fun physics demonstration where you get to burn stuff.  Just place some cotton in a syringe and press down quickly.

Voila!  Instant ignition. How hot does it get inside a fire syringe?

Let's assume you push down with 10 pounds (~44 newtons) of force over a distance of 10 centimeters.  While pushing you do work on the gas inside.  Work is equal to force times distance:

work = (44 newtons) × (10 cm) = 4.4 J.

A syringe with 0.25 cm2 cross-sectional area and a 20 cm length will contain roughly 5 milligrams of air. The heat capacity for the air in the container is about 1.0 J/g·K. From these numbers we can find the temperature of the air will rise by 9000 kelvin, giving a final temperature of 15,000 degrees Fahrenheit! For reference, the cigarette lighter burns at about 3000 degrees Fahrenheit, so the syringe is clearly hot enough to set the cotton on fire!

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

## Friday, May 3, 2013

### Dirty-sounding Physics Term of the Week 4

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

### I Love My Students....

We're covering relativity this week.  My students sent me this...

My day has officially been made.

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.

## Wednesday, May 1, 2013

### Scientific Paper of the Week

Mmm...I love me some fundamentals of quantum physics. Especially when they might lead to an experimentally falsifiable theory of quantum measurement and wave function collapse.

 These guys know what I'm talking about...

This week's Scientific Paper of the Week reviews how we might be able to do just that. Man, I really hope we come up with a more illuminating and experimentally falsifiable description of quantum measurement within my lifetime. Until then, Copenhagen interpretation me, baby!

Aaron Santos is a physicist and author of the books How Many Licks? Or How to Estimate Damn Near Anything and Ballparking: Practical Math for Impractical Sports Questions. Follow him on Twitter at @aarontsantos.