Recently having tied myself up in knots thinking fruitlessly about relativity and quantum theory, and embarrassed over how much Newtonian mechanics I've forgotten, I found relief through experimentation. I returned to a sport which gives me a "gut feeling" for how Newton's physics works, without making a single mathematical calculation.
Take my boomerang out of the closet. Take it to a large empty field. Test the wind by dropping a blade of grass. Throw the "rang" at an angle to the right of the approaching wind, watch its flight, and run if necessary to the spot where I "think" it will land.
Object: Catch the boomerang with bare hands before it hits the ground, preferably having thrown it so that it truly "comes back" to the place from which I launched it.
There is no way I could write the equations of motion of this amazing and enjoyable object thrown from my hand, let alone specify the initial conditions. Launch angle and speed, aerodynamics of the boomerang, variable wind conditions (easier on a calm day), air resistance, gravity. Presumably all I would need are Newton's laws and accurate initial conditions -- impossible in practice. And yet the problem can be solved!
I solve it by using .... hand-eye coordination? -- a sort of physical intuition and close attention to the boomerang's flight to "predict" where it will come down. I throw and watch it fly away. As it curves, I start running toward the general area I feel it will end up at. I must look like a crazy, lumbering squirrel as I adjust my path due to any wind gusts changing the flight path of the boomerang, or just to correct my previous wrong guesses.
If I'm lucky, I run back and forth a few feet and - wow! - it comes back to the point from which I launched it! If unlucky, I have to run flat out to try to get to it before it hits the ground. Diving catches are optional, depending on the condition of the field. The most humbling, however, is to have it come right back to where it started, ending in a spinning, slow descent, right into my hands, and fumble and drop it!
I may throw 20 or 30 times in a session, and I may be so lucky as catch 7 or 8 of these throws before they hit the ground. Not bad, "batting" .300, is it? Maybe I can reach .500 if I keep trying. If you've ever enjoyed playing baseball, especially the outfield, throwing a boomerang can be fun, albeit more challenging than catching a fly ball. More complicated physics, yet presenting me with problems I can solve without equations and computer programs, using my senses directly -- at least solve them some of the time!
What a good way for me to unwind from what to me is the incomprehensibility of quantum mechanics!
Boomerang Physics
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Mike Strand
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- Joined: Wed Jan 06, 2010 6:54 am
- Location: USA
Re: Boomerang Physics
hiccup
Last edited by Mike Strand on Thu Apr 07, 2011 8:48 pm, edited 1 time in total.
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Mike Strand
- Posts: 406
- Joined: Wed Jan 06, 2010 6:54 am
- Location: USA
Re: Boomerang Physics
Results of latest boomerang experiment: I caught 15 out of 30 throws. Newton's Laws appeared to be working, and the motions observed, while not always well predicted, validated my intuition. I did more running than I wanted to, which means I need to learn to throw better.
I got a little cocky at 7 for 12, fell behind, and didn't see .500 again until 14 for 28. I came close to calling it over with .500 in the bag. But then told myself, its only a game. Throw 29 was too fast and low, and I didn't get under the 'rang, even after a good sprint - 14 for 29. Throw 30 was just about perfect - ran a few yards half-way to my left, and it came down softly, and I concentrated and managed to keep it in my hands.
During this experiment, I dropped four easy catches, which is disappointing after you've made a decent throw, and you easily get under a vertically descending 'rang. One needs to concentrate fully during those last couple of seconds of the 'rang's descent. But to compensate, there were a few difficult catches, a couple with hands and chest, on the run, with the 'rang coming at me with a good horizontal component of velocity. The wind was variable, and dropping and watching grass blades before throwing turned out to be a good idea. 50 degrees to the right of the line of oncoming wind is the recommended launch angle, and you hope the wind either dies or holds its direction during the flight.
If I manage to do this 3 or 4 times a week, I may get back into shape. And it's a good break from GTR and QM.
I got a little cocky at 7 for 12, fell behind, and didn't see .500 again until 14 for 28. I came close to calling it over with .500 in the bag. But then told myself, its only a game. Throw 29 was too fast and low, and I didn't get under the 'rang, even after a good sprint - 14 for 29. Throw 30 was just about perfect - ran a few yards half-way to my left, and it came down softly, and I concentrated and managed to keep it in my hands.
During this experiment, I dropped four easy catches, which is disappointing after you've made a decent throw, and you easily get under a vertically descending 'rang. One needs to concentrate fully during those last couple of seconds of the 'rang's descent. But to compensate, there were a few difficult catches, a couple with hands and chest, on the run, with the 'rang coming at me with a good horizontal component of velocity. The wind was variable, and dropping and watching grass blades before throwing turned out to be a good idea. 50 degrees to the right of the line of oncoming wind is the recommended launch angle, and you hope the wind either dies or holds its direction during the flight.
If I manage to do this 3 or 4 times a week, I may get back into shape. And it's a good break from GTR and QM.
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Mike Strand
- Posts: 406
- Joined: Wed Jan 06, 2010 6:54 am
- Location: USA
Re: Boomerang Physics
Today I was happy for the exercise, but not a great success rate: 8 catches out of 30 throws. Several throws were so bad I just stared at the boomerang and watched it land, flat-footed, after a hapless sprint. I dropped a few good throws -- one came right down to me and I fumbled it for about 2 seconds before dropping it.
A couple of high points: Catching one on the run going away from me gave me 4 for 17. Also, I was 6 for 28 and caught the last two. Always a silver lining.
A couple of high points: Catching one on the run going away from me gave me 4 for 17. Also, I was 6 for 28 and caught the last two. Always a silver lining.
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Mike Strand
- Posts: 406
- Joined: Wed Jan 06, 2010 6:54 am
- Location: USA
Re: Boomerang Physics
Did better today, after falling and bruising ribs a couple of weeks ago, attempting to turn and run for a throw that flew over my head. My body got ahead of my feet. Got to keep those feet under me!
This evening the breeze was slight and steady, which eliminated one important "nuisance variable", and my throws were more often good than not. This meant only a few sprints to try to make a catch. Ended with 21 for 31 (.677), best yet. Missed a few easy catches, caught a few harder ones, but nothing spectacular. I planned on 30 throws, but the rule is to catch the last throw. At 20 for 29, I missed throw 30; luckily I caught throw 31.
The boomerang is in the air for about 7-9 seconds after I throw it.
If anyone would like to join me in this sport, go ahead, wherever you are, and report back to me on your experience. It's good exercise, and a fun way to solve Newtonian physics problems with intuition and physical effort. These problems cannot be solved with math, since there are too many variables and initial conditions that cannot be specified (identified and quantified), even though some people might know many of the basic equations.
A comfortable escape from the mysteries of quantum physics and relativity theory.
This evening the breeze was slight and steady, which eliminated one important "nuisance variable", and my throws were more often good than not. This meant only a few sprints to try to make a catch. Ended with 21 for 31 (.677), best yet. Missed a few easy catches, caught a few harder ones, but nothing spectacular. I planned on 30 throws, but the rule is to catch the last throw. At 20 for 29, I missed throw 30; luckily I caught throw 31.
The boomerang is in the air for about 7-9 seconds after I throw it.
If anyone would like to join me in this sport, go ahead, wherever you are, and report back to me on your experience. It's good exercise, and a fun way to solve Newtonian physics problems with intuition and physical effort. These problems cannot be solved with math, since there are too many variables and initial conditions that cannot be specified (identified and quantified), even though some people might know many of the basic equations.
A comfortable escape from the mysteries of quantum physics and relativity theory.