Wednesday, April 30, 2014
Aren't you Scared He Won't Speak English?
We just recorded Misael at two and a half responding to a hysterical series of questions. Last week he just responded "yeah" to every question posed in English, but now he intercalates "no" and will soon be actually answering questions so we had to record it quickly.
Tuesday, April 29, 2014
On Becoming Sinister
Mommy tells me that I was always right handed. The right got even more dominant when I broke my left arm in a swing parachuting accident at the age of 7. The trend continued at 17 when I fell off the railing on our deck and broke left radius and ulna once again.
I was so right handed by the time I started Grove City College that I was too predictable on the basketball and volleyball courts so I decided to take action. It's not only red shirt kindergartners who do things to push the competitive edge.
I was so right handed by the time I started Grove City College that I was too predictable on the basketball and volleyball courts so I decided to take action. It's not only red shirt kindergartners who do things to push the competitive edge.
Monday, April 28, 2014
New Videos from LrnFzx!
Inspired by SmarterEveryDay, I decided to put together a pair of videos this weekend and I posted them to YouTube. A definite improvement.
The first is a StoryReview on a kayak we bought
And the second a Review/Test of a new tool that came in the mail.
The first is a StoryReview on a kayak we bought
Our Children are the Stars of this One
Teach Fzx - How Many Volts?
We finally reached electric potential difference in Fzx class so I started with a question.
After reminding them that every standard outlet across the fruited plains of the US and Canada has a standard voltage, I asked them to give the value of that voltage. With answers ranging from 9 to 9,000 volts, there were only NINE Honors Physics students out of 60 who gave the correct answer of around 120V.
Is it really possible that so few students actually know that?
Then I asked about the voltage of an automobile battery. Most of these answers ranged from 100 V to 10,000 V with only a few answers under 100 V. FOUR students supplied correct answers between 12 and 15 V with two more coming in at 9 V.
Some argued vehemently that a car must have more voltage than the house because the car has to do so much more work to turn the engine over and start the car. I think it's a confusion of voltage - the energy supplied for each coulomb of charge - and power - the rate of use of energy. Depending on what's connected to it, the voltage source can supply large power or small power, depending on the current.
Now that I know that we are basically starting from zero knowledge of electricity, I can focus more properly on the basics.
.
.
.
.
One connected note - Public peer answers affect each other. The morning classes gave many more voltage values in the thousands for both questions and the afternoon class commonly answered in hundreds of volts. Both sets of answers were severely wrong, but the mode values were off by a factor of ten. I believe this to be a result of student conformity to earlier responses they heard.
After reminding them that every standard outlet across the fruited plains of the US and Canada has a standard voltage, I asked them to give the value of that voltage. With answers ranging from 9 to 9,000 volts, there were only NINE Honors Physics students out of 60 who gave the correct answer of around 120V.
Is it really possible that so few students actually know that?
Then I asked about the voltage of an automobile battery. Most of these answers ranged from 100 V to 10,000 V with only a few answers under 100 V. FOUR students supplied correct answers between 12 and 15 V with two more coming in at 9 V.
Some argued vehemently that a car must have more voltage than the house because the car has to do so much more work to turn the engine over and start the car. I think it's a confusion of voltage - the energy supplied for each coulomb of charge - and power - the rate of use of energy. Depending on what's connected to it, the voltage source can supply large power or small power, depending on the current.
Now that I know that we are basically starting from zero knowledge of electricity, I can focus more properly on the basics.
.
.
.
.
One connected note - Public peer answers affect each other. The morning classes gave many more voltage values in the thousands for both questions and the afternoon class commonly answered in hundreds of volts. Both sets of answers were severely wrong, but the mode values were off by a factor of ten. I believe this to be a result of student conformity to earlier responses they heard.
Sunday, April 27, 2014
Toddlers Organize!
One of the differences between our kids is the tendency to organize. Although neither one is a union leader orchestrating hunger strikes for better conditions in preschool, the two year old loves to line everything up in pretty little rows. Here is some of Misael's work.
A few weeks ago he built this vehicle train
Wednesday, April 23, 2014
SmarterEveryDay vs. LrnFzx
Check out the new video from SmarterEveryDay:
It has 2.3 million views in the four days since it was posted. My video on the same idea, posted to Lrn Fzx on November 19, 2012 has 170 views:
The first video has cute kids and a balloon and giggles and a helium voice from an established YouTube personality. It makes science fun and real.
The second has some old guy with a Steelers balloon
The second has some old guy with a Steelers balloon
Wednesday, April 16, 2014
All Science is Multiple Choice
We've all been taught the scientific method again and again:
Step 1 - Identify a problem or a ax question.
Step 2 - Propose an answer or a solution (hypothesis).
Step 3 - Devise a test for the hypothesis.
Step 4 - Test. Analyze. Conclude.
Step 5 - Communicate your results.
Step 6 - Repeat.
The steps of this method, like the ten commandments, are often numbered differently but communicate the same concepts. Not all science actually happens this way since we know that sudden leaps forward are sometimes attributed to dreams and sudden revelations, but the slow plodding process does us well on a daily basis.
The lock on my school locker won't open. I try it again. Then I check the locker number just to be sure I'm in the right place. Then I slow down and try it again. It still doesn't open, but practical jokes are common around here so my lock may have been replaced. One more time. Then I see my giggling friends and the eyes of several phones.
My motorcycle won't start. It could be the battery. Or the spark. Or the fuel. So I take on the limited number of possibilities and eliminate them one by one until I arrive at the solution. The bike starts and I head out for a great ride.
We use the process continuously without even realizing it. Scientists and engineers and business managers and medical researchers use it in a very specific form in order to gain knowledge, change treatment protocol, and improve efficiency.
No matter how we do it, however, we could easily summarize the process as a complicated multiple choice question. Once the question is determined, there is a limited number of possibilities and we test and eliminate each wrong answer.
In other words, the entire scientific endeavor is just like the SAT.
So the next time somebody asks me what I teach, I'm gonna proudly respond
"I teach Multiple Choice."
Step 1 - Identify a problem or a ax question.
Step 2 - Propose an answer or a solution (hypothesis).
Step 3 - Devise a test for the hypothesis.
Step 4 - Test. Analyze. Conclude.
Step 5 - Communicate your results.
Step 6 - Repeat.
The steps of this method, like the ten commandments, are often numbered differently but communicate the same concepts. Not all science actually happens this way since we know that sudden leaps forward are sometimes attributed to dreams and sudden revelations, but the slow plodding process does us well on a daily basis.
The lock on my school locker won't open. I try it again. Then I check the locker number just to be sure I'm in the right place. Then I slow down and try it again. It still doesn't open, but practical jokes are common around here so my lock may have been replaced. One more time. Then I see my giggling friends and the eyes of several phones.
My motorcycle won't start. It could be the battery. Or the spark. Or the fuel. So I take on the limited number of possibilities and eliminate them one by one until I arrive at the solution. The bike starts and I head out for a great ride.
We use the process continuously without even realizing it. Scientists and engineers and business managers and medical researchers use it in a very specific form in order to gain knowledge, change treatment protocol, and improve efficiency.
No matter how we do it, however, we could easily summarize the process as a complicated multiple choice question. Once the question is determined, there is a limited number of possibilities and we test and eliminate each wrong answer.
In other words, the entire scientific endeavor is just like the SAT.
So the next time somebody asks me what I teach, I'm gonna proudly respond
"I teach Multiple Choice."
Tuesday, April 15, 2014
Teach Fzx - Naming is NOT Understanding
There is a clear difference between naming and understanding and I see it in class every day. Inertia, for example, is a problem for physics students.
Following Aristotle from 350 BC and rejecting Galileo's "modern" science discovery 400 years past, my students consistently believe that in order to keep moving at a constant velocity there must be a larger forward force than backward force. This actually results in a forward net force that will increase speed. They're wrong. I've tried multiple choice and free body diagrams and fill in the blank; verbal and written formats - They're consistently wrong.
But they can fill in the blanks for "An object at rest ... and an object in motion ... unless ...." (will stay at rest ... will continue moving ... acted on by a force). So they can recite the basic Law of Inertia with a tiny bit of prompting but they have no idea that
Following Aristotle from 350 BC and rejecting Galileo's "modern" science discovery 400 years past, my students consistently believe that in order to keep moving at a constant velocity there must be a larger forward force than backward force. This actually results in a forward net force that will increase speed. They're wrong. I've tried multiple choice and free body diagrams and fill in the blank; verbal and written formats - They're consistently wrong.
But they can fill in the blanks for "An object at rest ... and an object in motion ... unless ...." (will stay at rest ... will continue moving ... acted on by a force). So they can recite the basic Law of Inertia with a tiny bit of prompting but they have no idea that
Monday, April 14, 2014
Teach Fzx - Newton's Third is Impossible
 |
| Newton, 1700, Genius |
Galileo had already
proposed the concept of inertia more than half a century earlier and Newton was
working forward from that idea. Newton knew that an object with smaller inertia (mass) accelerates proportionally more than an object with larger
inertia if the same net force is applied so he considered collisions between two
objects and only had a few choices.
A. The amount of inertia (mass) determines
which object applies a larger force to the other.
B. The speed of an object determines which applies
a larger force to the other.
C. The momentum of an object determines which
applies a larger force
D. Both objects will always apply the same size
force to each other no matter what.
My students can finish the sentence "For every action, there is ...."
Sunday, April 13, 2014
When Monessen Was Home
I took a long ride yesterday and ended up at our old house. A beautiful day and a child's nap called me and my bike to the road and I wanted to run to little Washington just because I hadn't been there for a long while. No plan after I got there, but the merge to the Fort Pitt Tunnel and the rush of the highway traffic is always an adventure.
I wandered the tiny town for a bit and then headed east on 70 toward Philly and NYC. The highway quickly bored me and I saw a pair of country roads so I took the next exit and hopped on the path. It paralleled the highway in a general sense but twisted and turned, rose and fell. This must have been the only road decades ago before the intrusion of the divided four lane and I really had to brake hard, shift fast, and check out all the old farmsteads.
Soon I saw signs for Charleroi where Dad used to work and Monongahela where we went to church. I took the road to Charleroi and wandered the old steel town which still has parallel one-way streets that used to support block upon block of small businesses.
I almost decided to head home after that, but I saw the sign for Monessen, crossed the bridge and found another pair of parallel one-way streets supporting even fewer active businesses. Having visited a few times in the past decades, I knew how to get to the old house and wanted to snap some images to share with my family.
I usually don't think I have memories of my early years, but along some of those streets I flashed on long walks that we took as a family in training for summer hikes. I remembered playing football for the first time at a neighbor's house and dragging some kid along who was trying to tackle me. I remember falling from a tree, getting scratched by our cat in heat, taking the snake for slithers in the back yard, and hitting up the corner store for Charleston Chews and baseball cards with that powdery stick of gum. Our first cat I named "Meow Mix" and one of her litters after all the characters in "Welcome Back Kotter." Later kittens were named after elven princesses in "The Lord of the Rings."
I talked to the owner and got a tour of the house about 15 years ago. Everything was the same inside. He told me that the big pine trees had started rotting and had to be taken down. I asked about the fireplace - it had just fallen apart over the years. I told him my Dad had built that railroad tie off-street parking space and he said "Well, that thing ain't goin' nowhere."
It's good to go back and remember sometimes. That was 1979.
I wandered the tiny town for a bit and then headed east on 70 toward Philly and NYC. The highway quickly bored me and I saw a pair of country roads so I took the next exit and hopped on the path. It paralleled the highway in a general sense but twisted and turned, rose and fell. This must have been the only road decades ago before the intrusion of the divided four lane and I really had to brake hard, shift fast, and check out all the old farmsteads.
Soon I saw signs for Charleroi where Dad used to work and Monongahela where we went to church. I took the road to Charleroi and wandered the old steel town which still has parallel one-way streets that used to support block upon block of small businesses.
I almost decided to head home after that, but I saw the sign for Monessen, crossed the bridge and found another pair of parallel one-way streets supporting even fewer active businesses. Having visited a few times in the past decades, I knew how to get to the old house and wanted to snap some images to share with my family.
It used to have huge pine trees near the road and no front porch.
Tough driveway for the winter
They've enclosed the porch and removed the outdoor fireplace.
They trust Dad's handiwork with the Camaro 35 years later.
I usually don't think I have memories of my early years, but along some of those streets I flashed on long walks that we took as a family in training for summer hikes. I remembered playing football for the first time at a neighbor's house and dragging some kid along who was trying to tackle me. I remember falling from a tree, getting scratched by our cat in heat, taking the snake for slithers in the back yard, and hitting up the corner store for Charleston Chews and baseball cards with that powdery stick of gum. Our first cat I named "Meow Mix" and one of her litters after all the characters in "Welcome Back Kotter." Later kittens were named after elven princesses in "The Lord of the Rings."
I talked to the owner and got a tour of the house about 15 years ago. Everything was the same inside. He told me that the big pine trees had started rotting and had to be taken down. I asked about the fireplace - it had just fallen apart over the years. I told him my Dad had built that railroad tie off-street parking space and he said "Well, that thing ain't goin' nowhere."
It's good to go back and remember sometimes. That was 1979.
Friday, April 11, 2014
Teach Fzx - Nobody Knows Nothin about the Atom
For many years, my Physics students have taken a quick quiz just before electrostatics:
"Sketch and label and atom and its parts. Use a modern model. Be specific and ask no questions" (The "ask no questions" clause was added after the class questions were leading more students to the correct answer.)
Keeping in mind that their first exposure to atoms is in primary school and that they study atomic theory again and again - earth science, biology, and chemistry - here are the results for my 60 to 100 Honors Physics students for each of the past years.
The Good News:
60-75% basically correct - protons and neutrons make up the nucleus. electrons doing something outside.
This percentage seems to have improved over the years. Perhaps this improvement is because there are more fans of "The Big Bang Theory" in my classes. Hopefully it is because the chemistry teachers know the results of this quiz and have taken steps to emphasize certain concepts.
They even sketch one or two electron cloud models every year!
The Bad News: The bad answers from most egregious to least. (25-40% )
1 to 5 - CELLS! - cell wall, cytoplasm, mitochondria, nucleus all labeled (2014 is the only exception to date)
1 to 5 - blank papers - IDK counts as blank
5 to 10 - circles labeled "atom" sometimes accompanied by a smiley face.
1 to 5 - with protons orbiting the nucleus or some such nonsense.
5 to 10 - with missing parts or labels - no neutrons or no protons or no nucleus.
More Bad News:
Today I asked the class "How big is the nucleus compared to the atom?" I surveyed the first class individually and asked publicly for their answers. The two basic answers were:
(90%) "The nucleus takes up most of the volume of the atom"
(10%) "The nucleus is a really small part of the atom"
For the second class, I modified the question to force them to give me a size fraction. All the students except one gave a nucleus to atom size fraction from 1/10 to 1/2. The exception was the lone student whose answer was one trillionth.
The third class seems to be the smartest. Or perhaps they are the ones who overhear the discussion from earlier classes and discuss it themselves. About 30% of those in attendance proposed fractions smaller than 1/1,000 but there were also two answers of 3/4 and 4/5.
Since the actual diameter of the atom is about 100,000 times larger than that of the nucleus, you can cube that for the volume ratio (1,000,000,000,000,000 = 1 x 1015 = one quadrillion). Most answers were way off.
I then asked them about "Rutherford's experiment with ... foil." Multiple students were immediately able to supply the missing "gold" in every class and many nodded vigorously when asked if they recognized the name of the experiment.
But as Richard Feynman's says of his father, "He knew the difference between knowing the name of something and knowing something."
"Sketch and label and atom and its parts. Use a modern model. Be specific and ask no questions" (The "ask no questions" clause was added after the class questions were leading more students to the correct answer.)
Keeping in mind that their first exposure to atoms is in primary school and that they study atomic theory again and again - earth science, biology, and chemistry - here are the results for my 60 to 100 Honors Physics students for each of the past years.
60-75% basically correct - protons and neutrons make up the nucleus. electrons doing something outside.
This percentage seems to have improved over the years. Perhaps this improvement is because there are more fans of "The Big Bang Theory" in my classes. Hopefully it is because the chemistry teachers know the results of this quiz and have taken steps to emphasize certain concepts.
They even sketch one or two electron cloud models every year!
http://goo.gl/JhBcZP
The Bad News: The bad answers from most egregious to least. (25-40% )
1 to 5 - CELLS! - cell wall, cytoplasm, mitochondria, nucleus all labeled (2014 is the only exception to date)
1 to 5 - blank papers - IDK counts as blank
5 to 10 - circles labeled "atom" sometimes accompanied by a smiley face.
1 to 5 - with protons orbiting the nucleus or some such nonsense.
5 to 10 - with missing parts or labels - no neutrons or no protons or no nucleus.
More Bad News:
Today I asked the class "How big is the nucleus compared to the atom?" I surveyed the first class individually and asked publicly for their answers. The two basic answers were:
(90%) "The nucleus takes up most of the volume of the atom"
(10%) "The nucleus is a really small part of the atom"
For the second class, I modified the question to force them to give me a size fraction. All the students except one gave a nucleus to atom size fraction from 1/10 to 1/2. The exception was the lone student whose answer was one trillionth.
The third class seems to be the smartest. Or perhaps they are the ones who overhear the discussion from earlier classes and discuss it themselves. About 30% of those in attendance proposed fractions smaller than 1/1,000 but there were also two answers of 3/4 and 4/5.
Since the actual diameter of the atom is about 100,000 times larger than that of the nucleus, you can cube that for the volume ratio (1,000,000,000,000,000 = 1 x 1015 = one quadrillion). Most answers were way off.
But as Richard Feynman's says of his father, "He knew the difference between knowing the name of something and knowing something."
Thursday, April 10, 2014
Center of Gravity Demo
There is a list of center of gravity demonstrations that we do in class to show the concept. One of them is the famous chair experiment and here it is from "All in the Family."
The same experiment can also be done without a chair and many boys still can't stand up. But some girls are also unsuccessful with both.
The standard physics explanation is that women can do it but men can't because of the difference in their weight distribution. Men are supposed to carry more weight in their shoulders and women in their hips so a woman's center of mass is lower and she can lift the chair.
I've never been completely satisfied with that explanation. We have never taken foot size to height ratios into account. Nor have we considered the fact that women's shoes tend to hug their feet more than men's shoes. Leg length to height ratios have never been compared either. There is no controlling of variables and no rigorous testing.
In other words, are this demonstration and the accompanying explanation good science or not?
The standard physics explanation is that women can do it but men can't because of the difference in their weight distribution. Men are supposed to carry more weight in their shoulders and women in their hips so a woman's center of mass is lower and she can lift the chair.
I've never been completely satisfied with that explanation. We have never taken foot size to height ratios into account. Nor have we considered the fact that women's shoes tend to hug their feet more than men's shoes. Leg length to height ratios have never been compared either. There is no controlling of variables and no rigorous testing.
In other words, are this demonstration and the accompanying explanation good science or not?
Over the Rail and into the River
In nice weather I often take a longer route to work for more pedal time. This morning I headed over the river to Lawrenceville and returned across the sidewalk of the 40th Street Bridge to Millvale.
As I pedaled up the bridge, the man walking toward me stubbornly remained in the middle of the sidewalk. I slowed down and clicked off my flashing headlight to avoid excessive annoyance on the part of the pedestrian.
As we passed, he stayed centered on the path and began to shout things like "Get off the sidewalk! Get back on the road! What's the helmet for, pussy?! Oooh, and you've got lights too!"
The mocking continued as I sped on up the hill. And that was it. Nothing else actually happened. But I recognized the young man as a former student at the high school - he hasn't changed.
Then again, maybe he has changed. An unprovoked verbal attack like that may represent an acceleration of stupidity. I could see him wearing a wife beater, beer in hand, smackin' his girlfriend around in front of her kids. He's the kind of boy-man who starts a bar fight over a bet.
Thinking back, I'm glad I didn't stop. Plenty of people carry weapons and some even taunt others just for the chance to use them.
And I don't think I'll be riding the sidewalk across bridges in the dark any more. He could have tossed me over the rail and into the river with a well-placed hip check.
As I pedaled up the bridge, the man walking toward me stubbornly remained in the middle of the sidewalk. I slowed down and clicked off my flashing headlight to avoid excessive annoyance on the part of the pedestrian.
As we passed, he stayed centered on the path and began to shout things like "Get off the sidewalk! Get back on the road! What's the helmet for, pussy?! Oooh, and you've got lights too!"
The mocking continued as I sped on up the hill. And that was it. Nothing else actually happened. But I recognized the young man as a former student at the high school - he hasn't changed.
Then again, maybe he has changed. An unprovoked verbal attack like that may represent an acceleration of stupidity. I could see him wearing a wife beater, beer in hand, smackin' his girlfriend around in front of her kids. He's the kind of boy-man who starts a bar fight over a bet.
Thinking back, I'm glad I didn't stop. Plenty of people carry weapons and some even taunt others just for the chance to use them.
And I don't think I'll be riding the sidewalk across bridges in the dark any more. He could have tossed me over the rail and into the river with a well-placed hip check.
Tuesday, April 1, 2014
Trash Trophy
In the spring of the year when neighbors are inspired to clean basement and attic, one heap of discarded materials in the alley behind a local Etna resident's home was begging to be plundered.
The first run home yielded 10 feet of inch-and-a-half square tubing from a clothing rack.
Our hero passed once again and, having exhausted all obvious valuables, flipped open a few boxes and happened upon a baseball trophy. Quickly hefting it, he casually dropped it into his bag and sauntered home.
The trophy sat on a dining room shelf for a few months as he admired the lines and the casting quality until a free weekend of contemplation prompted him to list the item for auction on ebay. Just six hours later, a few watchers, a pair of messages, and an offer of $1000 encouraged him to do some research.
It took some time, but the trophy was finally identified as a Spalding trophy from the 1920s with the likeness of Ty Cobb. It turns out that none were known to still exist until one surfaced at a famous auction of sports memorabilia in the early 1990s. The gavel price was almost $20,000.
Since then, a few more had been sold at auction and the price had stabilized at a bit more than $4,000 with the auction house taking 10% to 20% of the final price. It was time to hit the forums and find out if a sports memorabilia enthusiast would buy it directly. I ended the ebay auction early, received several angry messages from eager bidders, and continued my online search for a private buyer.
A few forum PMs and emails later, we agreed to a price of $3,300 plus $50 for shipping. I carefully packaged the trash trophy and sent it on to a new home.
The square tubing, after some welding, has become a support under the seating area of the kitchen island. The trophy now sits in a Washington state resident's display case awaiting the moment when father will bequeath it to son. We spent a free summer with family in Paraguay.
All from a good day of scavenging.
The first run home yielded 10 feet of inch-and-a-half square tubing from a clothing rack.
Our hero passed once again and, having exhausted all obvious valuables, flipped open a few boxes and happened upon a baseball trophy. Quickly hefting it, he casually dropped it into his bag and sauntered home.
The trophy sat on a dining room shelf for a few months as he admired the lines and the casting quality until a free weekend of contemplation prompted him to list the item for auction on ebay. Just six hours later, a few watchers, a pair of messages, and an offer of $1000 encouraged him to do some research.
It took some time, but the trophy was finally identified as a Spalding trophy from the 1920s with the likeness of Ty Cobb. It turns out that none were known to still exist until one surfaced at a famous auction of sports memorabilia in the early 1990s. The gavel price was almost $20,000.
Since then, a few more had been sold at auction and the price had stabilized at a bit more than $4,000 with the auction house taking 10% to 20% of the final price. It was time to hit the forums and find out if a sports memorabilia enthusiast would buy it directly. I ended the ebay auction early, received several angry messages from eager bidders, and continued my online search for a private buyer.
A few forum PMs and emails later, we agreed to a price of $3,300 plus $50 for shipping. I carefully packaged the trash trophy and sent it on to a new home.
The square tubing, after some welding, has become a support under the seating area of the kitchen island. The trophy now sits in a Washington state resident's display case awaiting the moment when father will bequeath it to son. We spent a free summer with family in Paraguay.
All from a good day of scavenging.
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