Physics Can Be So Distracting!

I've been the internet for a very, very long time, longer than a lot of people have been alive. In all those years, I've had battle scars from my battle with weirdos and cranks of all kinds, especially during the early wild, wild west days of unmoderated Usenet. Even now, I have to deal with them frequently, both online at various forums, and of course, the occasional stuff that tried to appear on this blog.

So you'll understand when I say that dealing with physics cranks is such a major distraction that, often, I see something and the first thing that comes to mind is just that!

I was at a wonderful Turkish restaurant last week, and I knew about this dish called Testi Kebab. I've seen it being served the last time I was at the same restaurant. I inquired about it, and our waiter described it and told us that if we wish to order that, they require a reservation a day in advance. This is because they bake the dish in this clay pot that is sealed. When they serve it, they literally break the pot and pour the content out. The broken clay pot is then tossed away, so they make a brand new clay pot each time this dish is ordered.

I immediately wanted to order that dish, and sure enough, we made a reservation for a group of people, and I ordered two of the dish, one large and one small, since there were 3 of us who wanted it. It was wonderful. The meat was lamb, and it came with vegetables stewed slowly in the sealed clay pot. After they broke the pots at our table, I asked if I could keep the broken pots, and they said yes.

I took them home, washed them, and they are now on display somewhere in my living room. But I have to tell you that as soon as I saw them when I got them home, the first thing that came across my mind was that I now have a couple of cracked pots in my house!

 

 

Oh well, I guess I just have to live with them! 😁

Zz.

Is 1/3 smaller than 1/4?

I'm sorry if this is old new, but I just found out about this recently.

I read a rather amusing account on why A&W 1/3 pounder lost out to McDonald's quarter pounder, even though they were both at the same price.

Confused why A&W's burgers weren't able to compete even though the burgers were priced the same as their competitors, Taubuman brought in a market research firm. 

The firm eventually conducted a focus group to discover the truth: participants were concerned about the price of the burger. "Why should we pay the same amount for a third of a pound of meat as we do for a quarter-pound of meat?" they asked. 

It turns out the majority of participants incorrectly believed one-third of a pound was actually smaller than a quarter of a pound. 

I hate to say it, but this is no longer surprising to me. I look back on my take on the public's understanding and perception of science, technology, and math, and the dismal state seems to have persisted. Nothing has changed. In fact, when I said this back in 2010 .... 

As scientists, we cannot forget this, because it explains the fickleness in the support that we get. That overwhelming support that is there one day can easily go away the next day, and not because of some scientific evidence, but possibly because someone else has better bells and whistles.

... I just never expected it to be illustrated so glaringly during the past few years. Many in the public do not have the ability evaluate the validity of a claim or evidence, and science can easily lose its support because someone else has a more attractive message, even without any valid evidence.

What are the odds that this is the root cause of our debacle today?

Zz.

Non-Newtonian Fluids On America's Test Kitchen Show

I've seen this episode of America's Test Kitchen before. It is Ep. 1 of Season 19. However, during a recent rerun of the show, I did a double take when I read the description of the show being displayed on my TV menu guide:

There as an entry that said "non-Newtonian fluids".

Like I said, I've seen this show before, at least twice, and I don't quite remember them mentioning this type of phenomenon.

When I saw the show again, I realized what it was. They had a "Science" segment on "fluids" such as ketchup and liquid thickened by corn starch. These two are common examples of..... you guessed it ... non-Newtonian fluids.

But interestingly enough, no where in the show or during this segment, did any mention of the phrase "non-Newtonian fluids" ever appeared. It was odd that they would discuss the phenomenon, but not mention the name given to it. Yet, it appears on the description for this episode. At the very least, giving the phenomenon a name not only allows someone who wants to know more about it something to Google on, but also relates known physics to a common observation.

Or maybe they don't want to mention it so as not to scare away their audience?

Zz.

The Physics Of Baking Pizza

For those who are purist and prefer the thin-crust, Neopolitano-style pizza, this one might be right up your alley.

This preprint on ArXiv tackles the question on whether baking such pizza is better done in a stone over rather than the standard metal ovens. Which one do you think will win?

Stone ovens heat up to very high temperatures, higher than typical home ovens. But ceramic or stone surface also has low thermal conductivity while having a high specific heat. It means that it retains heat longer and does not cause the dough to burn. It is why this is also the preferred way to bake rustic, crusty bread.

I guess we all just have to build a brick pizza oven in our backyards! :)

Zz.

Drilling In The Importance Of Units, Via A Banana Bread

For some odd reasons, intro physics students somehow can't get it into their heads the importance of having units in their answers whenever they are called for. And they also don't tend to see why carrying their units during a calculation can help them check if they are doing things correctly.

I've had constant issues with students not including units in their solutions. Even after I emphasize its importance, and even after I explain why it is important, I still constantly get answers, even in exams, of just a number without any units for length, speed, etc...

So one day, at the beginning of a new session, I decided to try something that I hope would be memorable to the students. I normally have between 10 to 20 students in a class. So on the first day of class, I baked a loaf of banana bread (I am actually a decent baker) and brought it to class. I cut the up into enough pieces for all the students, warning them that it has nuts and not gluten free, in case there are students with such allergies.

I let them enjoy the banana bread and then, I told them I baked it. They were impressed. Then I said that I'll give them the recipe if they want to bake this on their own. This is what I gave them:

• ¹⁄₂ butter
• 1 sugar
• 2 eggs, beaten
• 4 bananas, finely crushed
• 1 ¹⁄₂ flour
• 1 baking soda
• ¹⁄₂ salt
• ¹⁄₂ vanilla

I then included the rest of the instruction, but that is not relevant here.

Of course, within a minute, I had students telling me that this recipe is not complete and vague. "What is half butter and one sugar?" someone asked.

"Oh, you mean that you need the UNITS of measure for these ingredients to make the banana bread?" I innocently asked. "Does that mean that without knowing if these are 1/2 cup, or 1 teaspoon, or 1 tablespoon, these number really a vague and meaningless?" I continued.

That was when the students realized that they just had a lesson. The lesson here being that the need to know the units of measure is (i) necessary and that (ii) it isn't exclusive only to physics, and that we all have been using these units of measure everyday without realizing it. Without such units, a lot of things won't make sense.

I can't claim that this exercise was effective, but I did notice that I saw a significantly lower occurrences of missing units in the students homework and exams. The few times that this did occur, the only comment that I wrote next to the number with the missing units was "Banana bread!"


:)

Zz.

Space Coffee

It's amazing how much physics and engineering go into just getting the ISS occupants to have their cup of Joe while on board the space station.



They should just open a Starbucks franchise up there. It would have been easier!

Zz.

The Awesomest Physics Cake Ever?

I don't know if it is, but it certainly takes the cake (pun intended) for being quite creative! I wouldn't mind getting a cake that looks like that, or some variation of it with some condensed matter theme or accelerator physics theme......

Hum... I think I've come up with an idea for something. Wonder if my local bakery can make it?

Zz.

Explosive Beer Trick Explained

If you were ever half-drunk at a bar and started to wonder the physics of that explosive beer trick, now your curiosity can be set to rest.

But of course, no funding agency will pay for someone to study the neat tricks one can do with beer. So there is a more "useful" consequence to this.

Explaining this phenomenon may make you the life of your next party, but Rodriguez-Rodriguez and his colleagues studied beer in order to understand bigger-picture gaseous eruptions. One example is the Lake Nyos disaster in Cameroon. Volcanic activity under this lake dissolves carbon dioxide in the water. In 1986, the lake rapidly degassed a large amount of carbon dioxide all at once, suffocating 1,700 people and thousands more livestock. This rapid degassing event, possibly caused by a landslide, could share similar physics with an erupting beer bottle.

Like I've already said many time, a lot of things are inter-related.

Zz.

The Physics Of Toasty Buns

It's summer (at least, here in the northern hemisphere), and lots of outdoor grilling goes on. So what a timely article on the secret to getting proper grilling of food.

At high temperatures -- about 400 degrees and up -- a substantial part of the heat that reaches the food arrives in the form of infrared light waves rather than via hot air or steam.

The higher the temperature, the bigger the part that radiant heat plays in cooking. But this form of heat interacts with color in a profound way.
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A silvery, mirror-like fish skin is even more reflective than a white car. About 90 percent of the radiant heat striking it simply bounces away. Because only around 10 percent of the energy sinks in and warms the fish, cooking initially creeps along slowly but steadily.

That changes rapidly, however, as soon as the food gets hot enough to brown. It's like changing from a white shirt to a black shirt on a sunny summer day.

As the food darkens, that 10 percent of energy absorbed rises by leaps and bounds, and the temperature at the surface of the food soars.

So learn your physics to understand how to be good in grilling! :)

Zz.

Physics And Your Food Blender

I've mentioned several times on here on the effort to clearly demonstrate how physics is at work in the world of gastronomy. This is not entirely there, but certainly related to it. It is a Wired article on how the blender works, including a video that demonstrate what happens during its operation.

Question is, will it help me to make a better margarita? :)

Zz.

"Sticky physics of joy: On the dissolution of spherical candies"

Anyone reading this blog for any considerable period of time would know that I love reading or solving "mundane" problems. This one might barely qualify as one, I think. The authors are studying the "dissolution" of spherical-shaped candies.

Abstract: Assuming a constant mass-decrease per unit-surface and -time we provide a very simplistic model for the dissolution process of spherical candies. The aim is to investigate the quantitative behavior of the dissolution process throughout the act of eating the candy. In our model we do not take any microscopic mechanism of the dissolution process into account, but rather provide an estimate which is based on easy-to-follow calculations. Having obtained a description based on this calculation, we confirm the assumed behavior by providing experimental data of the dissolution process. Besides a deviation from our prediction caused by the production process of the candies below a diameter of 2 mm, we find good agreement with our model-based expectations. Serious questions on the optimal strategy of enjoying a candy will be addressed, like whether it is wise to split the candy by breaking it with the teeth or not.

In any case, I have to admit that I was snickering almost throughout the entire paper, especially the conclusion.

Finally we would like to address the question proposed in the very beginning of this study: What is the best strategy of eating such a candy? As so often, the answer depends on what the person enjoying the candy considers as the optimum. If the time the candy lives should be maximized, the eater of the candy should try to maintain the spherical shape of the candy by all costs. Since the e ect of mass transfer is driven by the surface, and the sphere possesses the smallest surface for a given volume among all possible shapes [5], any deviation of the spherical shape increases the process of losing mass. In particular, breaking the candy with the teeth enlarges the surface by a huge amount, making the candy vanish faster. Thus, from this point of view one should carefully try to keep the candy as spherical as possible. But there is another way to look at it: Suppose you break the candy with your teeth in many pieces. The surface becomes big, and in an instant the mass that is transferred away from the fragments becomes huge as well. This might amplify the effect of tastiness and joy, even though the life-time of the candy has become considerably short in this approach. Even though we now know how candies dissolve in time we stress that the best thing to do when eating a candy is to forget about these considerations, since they draw your attention away from what candies are made for: enjoyment.

C'mon, now. How could you not giggle when reading something like that in a physics paper? I'm only human! :)

I wouldn't be surprised if this gets nominated or even win the Ig Nobel Prize.

Zz.

Someone At Wok 'N Fire Knows Quantum Mechanics?

So there's a chain of restaurant in the Chicagoland area called Wok 'N Fire. It's a more upscale, modern Japanese/Thai/Chinese/etc.. Asian cuisine. The food isn't bad, if you don't mind it with a modern twist.

I'm on their mailing list, mainly because periodically they give out coupons (we love coupons!). I got one just today, and lo and behold, when I opened my e-mail, I saw this image!

The equation under the pie charts is the Schrodinger equation for a free particle! Well, it is missing the Psi(r,t) on the right hand side of the equation, but then again, when was the last time you see such a physics equation on a restaurant coupon?! :)

I wonder if I get a free appetizer if I identify the equation, thus revealing to the restaurant staff what a nerd I am?

Zz.

Measuring The Speed Of Light - Using Chocolates!

Those fun folk at JLab are at it again. This time, they'll demonstrate how you can measure the speed of light using a microwave, a ruler, and a LARGE bar of chocolate!




OK, I love them! There, I admitted it! It's the chocolate that pushed me over. :)

Zz.

The Physics of Guinness Beer

Physics and beer... I know to some people (you know who you are, college kids!), that's a definition of heaven. :)

This article, video, and paper should be up a lot of people's alley. It discusses the physics of Guinness beer, and tries to tackle some very profound questions:

For example, look closely at a pint of Guinness and tell me: do the bubbles go up, or do the bubbles go down? Why is the head coloured the way it is? Is beer foam a gas, liquid or solid? I thought you might enjoy this little video as a follow up, where an Irish physicist discusses the "fizzics" of bubble formation in Guinness beer.

 There is a video link to the article, which I will also link to here:




And the paper[1] that was published in Physics of Fluids (I kid you not) can be obtained from here as well.

Zz.

[1] M. Robinson et al., Phys. Fluids v. 20, p.067101 (2008).

Tossing A Leaky Bottle

I mentioned previously the column "What Happens Next" in the issue of Physics Education journal. I am a fan of that column because I love thinking about these "mundane" problems or puzzles. We dealt with bouncing grapes in sodas last time.

This time, it is another good one from the May 2011 issue. You have a regular plastic water bottle, filled with water. You poke a hole close to the bottom of the bottle, and another hole close to the top. With both holes opened, the water will flow out of the bottom hole. You can stop that by closing the hole on top. See picture

















But what will happen if you toss the bottle of water up into the air?

I'll post the answer later, because I'm sure you might want to try this out yourself! :)

Zz.

Bouncing Grapes In Soda

Again, as I had mentioned before, I love these kinds of "mundane" experiments and finding the physics behind it.

In the March 2011 issue of Physics Education journal, the section on "What Happens Next?" dealt with a very common phenomenon that a lot of people have seen, most of them while sitting at a bar drinking beers. This time, the scenario uses grapes.

You have a glass of a carbonated drink. You drop an unpeeled grape into it. What happens next? Interestingly enough, similar to dropping raisins and peanuts into such carbonated drinks (or beer), the grape will start to sink, and then after some time, it will float back to the surface. This gets repeated over and over again.

But but happens if you drop a peeled grape? Will it act any differently?

And what is the explanation behind all this?

Just so I won't spoil the fun for those who want to offer their explanations, I won't post what the article in the journal has written (you can, of course, "cheat" and look it up yourself). I will make another follow-up post at a later date and reveal to you the explanation.

Zz.

Want Tender Asparagus? Use Physics!

So, being a foodie and also being a cook as a hobby, I already know about this, mainly because I watch a lot of cooking shows on TV.

Here's a cooking tip for asparagus. To know that you're getting only the tender part of the asparagus, apply physics by determining the "bending moment" (?) of the asparagus. How does one do that?

The first thing to remember about asparagus is that it is actually a tender shoot that was in the active and rapid process of turning itself into a woody stem before it was picked. The bottom part was already well on the way through the process, while the top part was still actively growing and is quite tender. From a materials perspective, those two parts have drastically different properties. The woody part is tough and resistant to breaking. It has the ability to bend a little without snapping, but is stiff enough to resist the bending. The tender, upper part is brittle and snaps easily. Most importantly, the tough part is able to withstand shear forces while the upper part cannot.
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The only trick is to apply your forces correctly so that the maximum shear stress appears at the woody end of the asparagus and the minimum shear stress appears at the tender end. If you do it the wrong way, you’ll just break off the tip. So grip the tip in one hand, about an inch from the end. With your other hand grip the other end of the asparagus as close to the cut as you can. Hold the tip steady in one hand and bend the cut end, making sure that the axis of rotation is between your index finger and thumb. The asparagus will snap right at the junction between tender and woody.

Physics, and food. What could be a better combination? Well.... maybe physics and Disney, but that's another blog! :)

Zz.

The Science of Cooking

Hey, remember way back when I mentioned the story that several haute cuisine and avant-garde chefs are coming to Harvard to participate in a gastronomy physics course? Well now we have a report on it.

In this exclusive interview with physicsworld.com, one of the course organizers, David Weitz, professor of physics and applied physics in Harvard's School of Engineering and Applied Sciences, explains how cooking and food provide neat reference points for studying a variety of complex phenomena – from foams and emulsions to supercooling and complex phase changes.

"It's been beneficial and enjoyable for all of us," he says of the course, which completed its first run at the end of last year. "I'm pretty sure the students really enjoy it [and] it's certainly a wonderful way to teach freshman physics."

You can view the video interview at the link given above or see it here:



Zz.

The Physics of Cooking Oils

More culinary-related item for you to digest {pun intended}. This time, we look at the physics and chemistry of cooking oil, including all that you wanted to know about the physics and chemistry of olive oil.

The nice thing about this article that is utterly lacking in many news articles is that they included references! I love that! We can at least double check, or read in greater detail, some of these things and look at the sources.

Zz.

Culinary Physics Coming to Harvard

It was only a couple of days ago that I pointed to an article on the Physics of Cooking. Now comes a news report that avant-garde chef Ferran Adrià will be joining other chefs in teaching a course in gastronomy physics at Harvard.

Over 13 weeks, Andrés and Adrià will teach multiple times, while such renowned chefs as Blue Hill's Dan Barber and another Michelin-starred chef from Spain, Joan Roca, will appear once. Students will attend chef demonstrations, physics lectures and labs that explain the structure and characteristics of a classic emulsion (a liquid dispersed into another liquid) and more recent inventions such as Adrià's famous foams (air bubbles surrounded by thin sheets of fluid).

With a greater understanding of the physical parameters of food, students will learn how to manipulate them. Ditto for the chefs. Much of the culinary invention in recent decades has been a result of trial and error rather than scientific research. Adrià is reported to have invented the foam after a friend gave him a canister of nitrous oxide with which to experiment. Andrés developed a hot and cold foie gras soup at Minibar not because he knew that liquids at different temperatures have different densities (he learned that later) but because he had seen the technique used in Irish coffee.

I've seen Adria at his restaurant in one of the episodes of "Bizarre Foods" on the Travel Channel. While there certainly is a lot of creativity (and science) involved in his food preparation and presentation, I must say that I kinda like my food to be more "natural" rather than processed that much. I can understand the foam and the various nifty sauces to enhance the food, but when it has been transformed that much, it no longer becomes that appealing to me. Of course, I'm sure these things are wonderfully delicious, but I guess that my preference has always been the non-pretentious ethnic and simpler ma-and-pa type of cuisine.

It will be interesting if Harvard would put video of these courses online.

Zz.