A stunning glassblowing demonstration at the Glass Factory in Cabo San Lucas, Mexico

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

In late April my wife Elaine and I went for a cruise on the Disney Wonder. On April 25 th I went on a Coastal Highlights tour of Cabo San Lucas.

 

There was a stunning demonstration at the Glass Factory. A tag team of two artisans produced a hummingbird and flower, like the one shown above.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The sequence of their cooperation is shown above.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

They also had other objects like sea turtles.  

 

What were you doing a decade ago?

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Every month I read an online amateur microscopy magazine called Micscape. This month’s issue only has three articles, but also indexed their March 2012 issue. And that issue had my construction article titled Building a double gooseneck white LED illuminator for a stereomicroscope using modular coolant hose.

 

As shown above, I used 1/4” Loc-Line coolant hose parts to attach an LED headlamp to my StereoZoom7 microscope pod. Loc-Line consists of snap-together ball and socket segments. My collection of photo equipment also includes a Grip-It triple arm clamp made from Loc-Line.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Joby has copied the ball and socket idea for their GorillaPod line of tabletop tripods (as shown above). The three legs on that little tripod can be wrapped around a vertical post or horizontal rail to support my little Nikon Coolpix L110 digital camera for travel photography.   

 

 

A striking materials science lab demonstration

On November 26, 2019 I blogged about Avoid falling on your face during a new product demonstration. That post got me thinking about a great metallurgy lab demonstration I had seen almost five decades ago at Carnegie Mellon University. We were shown a Charpy impact test machine and how much the energy to break a V-notched steel specimen varied with temperature. As shown above, the machine has a weighted pendulum which can be released to hit the 1 cm (0.394”) square specimen opposite the notch and measure absorbed energy via rebound height.

At a low temperature there just was a quiet click, the sample broke in two in a brittle fashion, and pieces flew across the room. The pendulum rose to almost the same height as it had started at (less than 10 J). At a high temperature the sample instead bent in a ductile manner. It did not even break completely and it absorbed lots of energy (over 100 J). Examples of intact and broken specimens are shown above.   

Let’s look at an example set of data for a conventional pressure vessel steel plate in the (L-T) orientation (from the ASM Metals Handbook Volume 8, Mechanical Testing, Ninth Edition, 1985 - Figure 3 on page 262). At – 78 C (-108 F), using dry ice and ethanol for cooling, it took just 5 J to break. At ice water temperature, 0 C (32 F), it took 97 J. At room temperature, 20 C (68 F), it took 143 J. At boiling water temperature 100 C (212  F) it took 200 Joules (J). The S-shaped curve has a transition from ductile behavior and high absorbed energy at high temperatures to brittle behavior and low absorbed energy at low temperatures. It is typical for steels.  

Back during World War II this transition was not well understood, and some spectacular brittle failures occurred in welded structures. As shown above, The T2 tanker SS Schenectady broke almost in two on a cold January 1943 day while it just was sitting at a dock in Portland, Oregon. Then in October 1944 a cylindrical tank in Cleveland, Ohio used for storing liquified natural gas broke and the resulting explosion killed 130 people and destroyed a square mile area.  

You can read more about the test in a web page from TWI (The Welding Institute) titled What is Charpy testing? You also can watch a five-minute YouTube video from Materials Science 2000.

Images of the Charpy test (from Laurens vanLieshout), test specimens (from Dumontierc), and the SS Schenectady all came from Wikimedia Commons.

Avoid falling on your face during a new product demonstration

On Thursday November 22, 2019 Elon Musk unveiled Tesla’s innovative new electric pickup – the Cybertruck.

A 14-minute video of the demonstration shows clips with the Cybertruck winning a tug of war against a Ford F-150 (9:00), and outrunning a Porsche 911 (9:35). But that’s not what many media reports led with.

Metaphorically he fell right on his face. Elon told his chief designer, Franz von Holzhausen, to throw a metal ball at the driver’s window (7:35). When he did, large circle of glass broke. Then Franz repeated the throw and also broke the passenger window (7:55). Mr. Musk should have followed the Law of Holes: 

“If you find yourself in a hole, stop digging”

So, an article that day in the Daily Beast by Anna Kaplan is titled Tesla Cybertruck windows shatter during Elon Musk’s durability demo. Another article in Forbes by John Koetsier is titled Tesla demo fail: ‘transparent metal’ armored glass smashed during Cybertruck reveal.

Earlier, at 6:15 in the video, there were comparative ball drop tests showing conventional glass failing at a height of 3 feet, while the Tesla glass survived a height of 10 feet. Why did they take the unnecessary risk of throwing balls at the windows? The drop test setup already was an effective prop.

Assuming the same balls were used, how much more severe of a test was a throw compared with a drop. We can calculate the velocity from a 10 foot drop to be 25.4 feet per second (17.3 mph) based on changing potential energy to kinetic energy (proportional to the velocity squared). I showed how to do that in a November 2, 2019 blog post titled A thought provoking how to book by Randall Munroe. A major league baseball pitcher can throw a 100 mph fastball. Even if Franz only threw at 50 mph, that would still be far worse than the drop test. A drop test is more controllable than a throw. The rush of adrenaline during the demo could make you throw harder than you did during a rehearsal.  

Folks in the news media are not like the rest of the audience, who just want a presentation to succeed. They are looking instead for something startling to gain attention – a Man bites Dog story headline rather than the usual  boring Dog bites Man. Don Henley described that perverse attitude in his 1982 song, Dirty Laundry (see YouTube video):

“I make my living off the evening news

Just give me something, something I can use

People love it when you lose,

They love dirty laundry”

A cartoon man falling was Photoshopped from an 1890 lithograph at the Library of Congress. A man biting a (hot) dog was taken from this image at Wikimedia Commons.

A simple geometry demonstration using crackers

Props used for demonstrations don’t have to be complicated or expensive to be effective. As is shown above, the Pythagorean theorem say that, for a right triangle, the square of the hypotenuse (c ) is equal to the sum of the squares of the other two sides (a and b).

In Bobby Mercer’s new book, Junk Drawer Geometry: 50 awesome activities that don’t cost a thing, he has a clever demonstration of it on page 60 using fifty square cheese crackers. (You can read it on Google Books). As shown above, this example is for a = 3, b = 4, and c = 5.  I used 1” square Kellogg’s Reduced Fat Cheez Its. Of course, you could instead use larger crackers like Saltines.

Junk Drawer Geometry was preceded by two other books by Mr. Mercer with the exact same subtitle on the topics of Physics (2014) and Chemistry (2016).

When you look on YouTube for demonstrations of that theorem you can find another version using square Starburst candies, one with 4.5 mm diameter bearing balls, and several using water in connected flat containers. In The Wizard of Oz the scarecrow incorrectly states the theorem as being for an isosceles triangle. So does Homer Simpson, but he gets corrected immediately.

An image illustrating the theorem was adapted from one at Wikimedia Commons.

Burning a prop dollhouse to demonstrate how a house fire occurs

It’s hard to understand exactly what variables control how a structure fire occurs (fire dynamics). One excellent way is a demonstration using a dollhouse – an inexpensive prop just 49” high, 32’ wide, 19” deep. Watch Allen Fitzpatrick in this three-minute YouTube video titled Salem firefighter demonstrates fire flow paths by burning down doll house.

At Modern Fire Behavior there is a an article from 2015 on a new style dollhouse with plans. There is a 25-page pdf file of Palmer’s Dollhouse with both plans and instructions for lessons.  

There is a 9-minute video titled Deputy Chief PJ Norwood demonstrating flow paths with this training prop, and a 24-minute video titled Doll House fire behavior, Birmingham Fire and Rescue.

 

Demonstration Speech: Using an air fryer to make homemade low-fat French fries

Here in Idaho we love potatoes, particularly French fries. The big problem with deep frying is that the potatoes pick up lots of oil. For example, a large serving (5.4 oz) of McDonalds French fries has 470 calories with 198 calories (40%) coming from fat. Assuming the fat is canola oil, that’s about one and a half tablespoons of oil.

If you instead make fries at home with an appliance called an air fryer, then you can cut the amount of oil by a factor of four. The potato sticks are sprayed with oil rather than submerged in it. An air fryer is a countertop forced convection oven which circulates hot air around the basket of food. Inside the oven there is a spiral heating element and a fan (as shown above).

Begin with 12 ounces of Russet Burbank potatoes – one jumbo or two large ones. Either peel them, or scrub the surface with a wet brush to remove dirt. Cut the potatoes into uniform slices, and then cut the slices into your favorite thickness of square sticks.

As shown above, there is a very large range of thicknesses.

Soak the potato sticks in a bowl of cold water for ten minutes to remove surface starch. Then dry them, using a salad spinner (as shown above) if you have one, or paper towels if you don’t.

Place the sticks in the air fryer basket, and spray them with cooking oil spray from an aerosol can. Cook at 380 F until browned and crisp. Depending on the thickness this may take ten to twenty minutes. (See Williams Sonoma recipes for shoestring and seasoned regular fries).  

Back in February 7, 2016 I blogged about a Demonstration Speech: A world of healthy snacks from your microwave. Tortilla chips were included. Don’t try to air fry tortillas – they will float to the top and hit the fan. A demonstration speech is project 3 in the advanced Toastmasters communication manual on Speaking to Inform. Back on December 9, 2012, at Six Minutes, Andrew Dlugan blogged about How to Master the Demonstration speech.

A cartoon for illustrating a humorous ‘how to’ speech

On April 17, 2018 Doug Savage had a Savage Chickens cartoon titled The Right Way. It goes perfectly with the following story, which I told slightly differently in a blog post on February 22, 2011 titled Return of the Table Topics Bunny:

Back in the early 1980s I had a two-story condo and a curious little black kitten named Finster. On a late-spring weekend day I opened windows for the upstairs master bedroom (front) and bathroom (rear) for cross ventilation. Then I left to run errands for a couple hours. When I returned and opened the front door, I found a mound of toilet paper on the landing. A trail led all the way up the stairs, and into the bathroom. Finster obviously had jumped on the windowsill to look out. As he jumped back down he had brushed the toilet paper roll in the holder on the back wall, and it began to rotate and unroll. Once he got it started he just kept unrolling it and playing. I turned the roll around to feed out underhand rather than overhand. Then I never had that problem again.

How would you line the sloping walls of a large irrigation canal with concrete?

Near where I live there is a large road and intersection construction project in progress. The intersection of Cole Road and Lake Hazel Road is being redone, and Lake Hazel Road will be extended eastward, and cross over the ~45 foot wide, century old, New York Canal via a bridge (which has not been built yet). The New York Canal takes Boise Project water from the Boise River to Lake Lowell in Nampa. It runs for ~40 miles. A few days ago a crew from the Concrete Placing Co. was also finishing lining the canal walls upstream and beneath the bridge. Lining the canal is less than 10% of the road project.

Lining the flat canal bottom is like a bigger version of putting in a sidewalk, driveway, or patio. You likely are familiar with that. The area is dug out, and the edges of the patio are walled with forms to contain the concrete. Then concrete is brought to the site by a mixer transport truck, and delivered via an attached chute (or with wheelbarrows). As is shown above, two guys use a 2x4 board as a screed to strike off the top of the concrete level with the tops of the forms. Then the top can be finished further with a float and edger.  

If you wanted to demonstrate ‘striking off’ to a small audience you might use a 9” square cake pan as the form, a 12” long ruler as the screed, and a granular solid like kitty litter to represent concrete. Pictures or videos work better for a larger audience.

What about the sides of the canal? As shown above (viewed from one bank looking southeast) the sides were divided into panels ~12 feet wide. Half of them were poured using forms, and then the other half were filled in. You can see the welded steel wire reinforcement mesh laid where the new concrete will be placed. A chute from the concrete truck delivers a very stiff mix. Then a Deere tracked excavator uses a pair of ropes to pull a metal screed rod up the wall starting from the canal bottom. That rod is guided by two men using the panels already on both sides to support the ends. You also can see a concrete abutment for the new bridge at the very right.

The image of screeding came from Wikimedia Commons.

Wonderful storytelling - a prop demonstration early in the movie Deepwater Horizon

I just borrowed the DVD of Deepwater Horizon from my friendly local public library and watched last year’s big-budget Hollywood biopic disaster (and even IMAX) movie. What impressed me most was the brief prop demonstration shown above in a one-minute YouTube video. At the breakfast table Mike Williams little daughter Sydney jams a brass gizmo into the bottom of a full Coke can, and then squirts honey into the 'straw' on top. (NPR took note of that demo in their movie review).

If you were wondering how people possibly could drill a well into a pressurized gas and oil deposit, they just showed you the answer to your question - it’s a column of ‘mud.’ You didn’t have to go to Wikipedia and look up the page for Drilling fluid, and read the section under Control formation pressures. And then you saw the “well” go out of control and blow out.    

That’s effective storytelling - show rather than just tell. It reminded me of how another complicated story instead was told poorly - David Lynch’s 1984 science fiction epic Dune. It was based on Frank Herbert’s long 1965 novel about a revolt on the desert planet of Arrakis. A 2011 article at The MARY SUE showed both pages from The Glossary that came with Dune... The Movie. As we walked into the theater, they handed it to us. Here are two examples from that glossary:

MELANGE (May-lahnj): the “spice of spices’” the crop for which Arrakis is the unique source. The spice, noted for its geriatric qualities, is of great importance in empowering the Guild Navigators with the ability to “fold space,” thus uniting the Universe under the Emperor.

SANDWORM (known as Shai-Hulud): Sandworm of Arrakis. Sandworms grow to enormous length. Some are 1500 feet long and 125 feet high.; they live to great age, unless drowned in water, which is poisonous to them. 

But If you hadn’t previously read the novel, you still were really lost for the next two hours and seventeen minutes. Too much about that strange world was left untold or unsaid.

Watch a teaser from Deepwater Horizon that cuts between the tabletop demo and the following disaster.   

How to tie your shoelaces is a good topic for a demonstration speech

Back in 2011 there was a three-minute TED talk by Terry Moore on How to tie your shoes that you can watch at YouTube. The Wikipedia article on shoelaces mentions that there are two common ways of tying them – the square knot or the less effective granny knot.

Although a lot has been written, there always is more to be learned. On April 11th there was a news article from the University of California at Berkeley titled Shoe-string theory: Science shows why shoelaces come untied. Back on September 23, 2015 there was another article at Gizmodo by Jennifer Ouellette titled What’s the best way to tie your shoes? Physics may have the answer. You can read the article she referred to about Untangling the mechanics and topology in the frictional response of long overhand elastic knots.

Special bubble laces like the New Balance Sure Laces shown above are one way to reduce the annoying need for re-tying.

An image of Jeremy Brockie, forward for the New Zealand All Whites football team, came from Wikimedia Commons.

Some props are so inexpensive that you can give one to each member of your audience

Don’t believe me? Look at this UNESCO web page on how Simple toys make learning science fun. Arvind Gupta shows how to flatten one end of a plastic straw and make two diagonal scissor cuts to form a double reed. Presto - a magical straw flute!




Watch a 1-1/2 minute YouTube video on the straw flute. Also watch a wonderful 15-1/2-minute TED talk on Turning trash into toys for learning. At 10:05 he makes the flute. For even more you can watch his 1 hour and 10 minute talk from the 2016 Research Scholars Day at IIT on Making Science Fun. (Here the flute is shown at 21:30).

Poking holes in the competition with a product demonstration of pickup truck beds

Sometimes a demonstration is the best way to get your point across. General Motors recently released this three-minute YouTube video comparing how the  “high-strength military-grade aluminum alloy” bed of a Ford F-150 compared with the steel bed of their Chevrolet Silverado. It is effective because they dropped both very heavy concrete landscaping blocks and empty toolboxes.

The ad campaign was covered by USA Today, Forbes, and Truck YEAH! 

WHO knows how to wash your hands - an excellent demonstration speech topic

Are you supposed to give a demonstration speech for a class or the Speaking to Inform manual at your Toastmasters International club?  The World Health Organization (WHO) has a solution. They have excellent information for talking about hand hygiene.

A good starting point is their seven-page pamphlet on Hand Hygiene: Why, How & When? There is a poster on How to Handwash? Also see their web page Clean Care is Safer Care.

There also is is a 14-minute YouTube video on Hand Hygiene posted by the New England Journal of Medicine. Detailed hand moves are shown starting at 6:15. The information is presented in clinical jargon though. If you want a clearer, funkier Philadelphia version, look at the six-minute Wash “Em - Hand Hygiene Music Video from Thomas Jefferson University Hospitals. They show the hand moves starting at 3:00. (The video was inspired by Michael Jackson’s song Beat It). Even more hand and dance moves are shown in another four-minute video Hand hygiene from rubbing to dancing. 

I found this topic via an article on page D1 of the April 19th Wall Street Journal by Sumath Reddy titled The right way to wash hands: A scientific inquiry. It also is discussed in a press release about a magazine article titled A Pragmatic Randomized Controlled Trial of 6-Step vs 3-Step Hand Hygiene Technique in Acute Hospital Care in the United Kingdom whose abstract is at PubMed. 

The image of hand washing came from Wikimedia Commons.

Giving the worst lecture ever

Yesterday at Faculty Focus there was an article by Amy Blanding, Kealin McCabe, and Heather Smith from the University of Northern British Columbia titled The Worst Lecture Ever. It described beginning a course on presentation skills with a series of bad examples:

“We held the Worst Lecture Competition during the first full week of classes. The instructors and a graduate student competed for the Worst Lecture award, while students evaluated and voted for the worst lecture. 

Drawing on literature about effective presentations as well as personal feedback and our own experiences, we identified characteristics of the worst presentations. Then we divided those characteristics among ourselves, determined the personas we would adopt, and prepared to deliver the worst possible lecture. 

Heather presented a lecture about her cats. With slides full of cat photos and the enthusiasm of a devout cat lover, she shared plenty of useless facts and deviated from the topic to include photos of her trip to Australia. Heather was disorganized, unprepared, and tangential. She dressed sloppily, included quotes without citations, and cited problematic sources. On the plus side, she did have a clear learning objective. Unfortunately, she didn’t meet it… perhaps because she ran over the allotted time.”

Providing bad examples can be a humorous way to teach. I’ve previously blogged about Mixing up clear English and turning it into mud and Don’t be a “Flip Chart Charlie.”

The image was adapted from a 1944 drawing of a bomb lecture by Victor Alfred Lundy found at the Library of Congress.

Demonstration speech by Dave Lieber about Starbucks hot drink cup sizes

One of the joys of public speaking is finding excellent speakers you hadn’t seen before. Dave Lieber writes a column for consumers in The Dallas Morning News. His other web site is Watchdog Nation. Dave his discussed how Starbucks has their own private jargon for sizes that mixes English, Spanish, and Italian.  


Watch him in a YouTube video on Dave Lieber & Watchdog Nation Share the Starbucks Secret on TV (including how to drink free coffee there). His demonstration is humorous and memorable. It might be even better if he also pointed out that the cup sizes increase in steps of 4 ounces (a half-cup) as is shown below.

Demonstration Speech: A world of healthy snacks from your microwave

It’s Superbowl Sunday, so this afternoon and evening Americans will be consuming lots of greasy, salty snacks while watching the game on television.

Several years ago I gave a demonstration speech at my Toastmasters club that showed how to use a microwave oven to make healthier snacks. I showed them before and after cooking, and then passed around bags with samples.

Popcorn is one snack food that can be made healthier. As shown above, a plastic popper lets you use bulk popcorn without the fat found in those overpriced commercial bags. Then you can add spices like cayenne pepper, curry powder, or Chinese five-spice, salt, and some butter or margarine.

You can microwave a pair of tortillas on a dinner plate to make your own chips. Cook for thirty seconds, then turn them over and repeat. Regular tortillas might take about four minutes, while extra thin ones just about two. You can begin by rubbing a small amount of oil between the tortillas, and then salting them lightly. Break them into quarters after cooking.

You also can cook an Indian papadum on a dinner plate. Indian markets stock packages of these in several spicy flavors.

As shown above, you even can cook four Indonesian krupuk at a time. (Both uncooked and cooked ones are shown). Experiment to get the correct cooking time. You want the whole cracker to puff up (no raw edges), but don’t want to start burning them.
 

Prop demonstrations during lectures increase student performance in biology courses

Simple props can help present complex concepts. For example, a twisted cord on ear bud headphones can be used to demonstrate DNA replication, as described here.

A recent magazine article by F.  Tamari, K. M. Bonney and K. Polizzotto of the Kingsborough Community College in Brooklyn discussed how Prop Demonstrations in Biology Lectures Facilitate Student Learning and Performance. It appeared in the Journal of Microbiology & Biology Education, May 2015, vol. 16 No. 1, pages 6 to 12.

Table 3 of that article showed significantly higher scores on questions for students who had seen five demonstrations (blue) than those who had not (yellow), as is shown above in a bar chart.   

What’s your speaking style more like: Teppanyaki, Flambé, or Flying Greens?

My last post, Sizzle or Steak? Both!, got me thinking about restaurants and how having a unique speaking style (perhaps involving props) can add to your presentations. At one extreme is teppanyaki, the Japanese steakhouse typified in the U.S. by the Benihana restaurant chain. The chef puts on a big show of grilling the meal in front of his waiting customers. (On Saturday Night Live John Belushi parodied it in a comedy skit called Samurai Hit Man). It takes a lot of equipment to manage this. The speech equivalent would be a motivational speaker doing a multimedia spectacular in a large venue.

Less equipment is required for flambé, a table side flaming style involving igniting liqueur like for the Crêpe Suzzette dessert shown above. (The Greek restaurant cheese version is flaming saganaki). Both still are fancy productions involving added equipment and fire risks.

The most minimal but ingenious style is a Thai stir-fry dish called Flying Greens. It was described back in 1989 in a book called Madhur Jaffrey’s Far Eastern Cookery. Reportedly a young chef in an open-air restaurant up in Phitsanulok had been preparing swamp cabbage (pak bung) with garlic and oyster sauce. He tried tossing the greens up in the air from his wok before serving them. Soon he was throwing them for 20 feet. Finally he began throwing them across the street, where his partner adroitly caught them on a serving platter, and grandly presented them to waiting customers. There’s no extra equipment here at all, just teamwork. 

During his lectures MIT physics professor Walter Lewin did something different by sometimes pushing rather than pulling the chalk in his hand. The fourth most commonly viewed post on this blog is about How can you easily draw dotted chalk lines on a blackboard?

Images of Benihana, Crêpe Suzette, and a wok all came from Wikimedia Commons.