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Wednesday, March 19, 2014

The Ripples of Your Life

Greg Louganis is one of the most decorated Olympic divers in U.S. history. Every time he dives into the water, his impact sends out waves (ripples) of energy that carry onward. This same principle applies to life. He's had an immensely successful career and life. Yet, through all this international success, he has carried one mantra with him that his mother instilled in him...
 
"Make everywhere you go better because you were there."
 
This is how he measures his success. I admire him and try to emulate that in my daily life. I'd like you to share one time when you feel you had a positive impact on your surroundings (the people or the environment) AND one time when you didn't have as positive an impact as you could have had.
 
Choose something meaningful (I picked up a bottle at the beach isn't quite what we're looking for -- although I definitely admire it!). Be honest with yourself. Since your responses might be somewhat personal, email your responses to me -- you needn't put them on the blog. As you go out into the broader community and world during our Spring Break, bear in mind Louganis's words. Leave the world better for you having been here.
 
I'll start us off....I try to be a good neighbor by being friendly and helpful. Sometimes, it's just deliberately making eye contact and giving a smile, which helps add a sense of community and goodwill to our neighborhood because others respond in kind.
Recently while teaching, some middle school students were making noise outside. I made a snide/sacrastic comment about it, which was unnecessary and I regretted because of the example it set to my students in the class. It was a small moment but sometimes those small moments (good ones or bad ones) are the ones that have a lasting impact. I was bummed about my reaction aftterwards, but I'll try better next time.
 
Have a wonderful and well-deserved break! :) Mr. R

Tuesday, March 11, 2014

The Brown Note


There's no way to put this delicately...rumor has it that a certain low frequency tone can cause a person to, well, lose it! The Mythbusters put this so called "BROWN NOTE" to the test. Watch the clip at right (and notice their lower-half wardrobe choice!), and tell me everything you observe about the following points.
For each, make sure to reference any relevant characteristics of sound (period, frequency, wavelength, wavespeed, or amplitude/pressure level).

1. The huge speaker drivers (the vibrating part of the speaker) are oscillating back and forth. Based on what you see them doing, what characteristics will the sound wave have that they produce? Why?

2. Toward the end, the Mythbusters and the audio guys mention an impact the sound waves had on Adam's breathing (Adam the Mythbuster, not Feldman!). What was this impact and why did it happen?

Lastly, answer this...why would low frequency waves (rather than high frequency) be more likely to have this physical effect on you? (Harken back to "Hey, Baby. How you Doin'?")




Monday, March 3, 2014

I Hate to Sound Dense, but...

As with light, so with sound. Well, not always, but there are a few parallels, and one of those parallels is speed. The material (or medium) that sound passes through affects its speed. How so?

For a benchmark, let's use the speed of sound in air at the beach in Malibu on sunny, 70-degree day -- 1,125 feet/sec (666 mph), also known as Mach 1.

How will the speed of a given sound change (FASTER, SLOWER, NO CHANGE) in the following scenarios:

...on top of Mount Everest?
...submerged in a pool?
...through a wall?
...in Florida (same air temperature as Malibu, at sea leavel, but much more humid)?
...in space?

Excluding space, pick the option above that you think will transmit sound waves fastest, and explain WHY.