ewmon

You're looking for the frequency for its efficient transfer energy into the object — the algae's "resonant frequency" or some other energy transfer maxima. The first method considers the media, the second method considers the object's resonant frequency. I don't know how valid this method is (and I forget where I learned it), but one method is to determine the wavelength that's twice the width of the object you want to excite for the media through which the sound waves are traveling. For example, to break a wine glass with a diameter of 3 inches (¼ feet) in air would experience a energy transfer maxima at 1,126 ft/ sec / 2×¼ feet = 2,252 Hertz. I don't know if this works with "soft" objects, such as algae. I'm thinking that these algae are in water, so use the speed of sound in water. You may want to target the algae themselves or, say, its organelles such as mitochondria, etc. So, by this method, if the algae is, say, 5 micrometers in diameter, and the speed of sound in water is 1,500 meters/second, the resonant frequency would be 1,500 m/s / 2×0.000005 m = 150 MHz, which is the high-frequency band for ultrasound. This video shows another method that uses the object's natural resonant frequency, but we can't easily tickle some algae and measure their resonant frequency (or can we?). This method determines that the glass's resonant frequency as 337.5 Hz (cycles/second). It's an answer much lower than the frequency found by the first method. If you divide 1,126 ft/sec (the speed of sound in air at room temp) by 337.5 Hertz (or cycles), you'll get 3.34 feet per cycle (meaning 3.34 feet between compressions). This wavelength equals 40 inches, half of which is 20 inches, which is obviously much greater than the diameter of the wine glass. So, this is a frequency different from the first method. Also note that the video shows sound waves of about 1-inch wavelength, which corresponds to about 15,000 Hz, which is much different than the stated 337.5 Hz. In reality, the compressions are much farther apart and traveling much faster than shown.

Same thing with driving a car, voting in public elections, attaining knowledge, etc. The laws don't guarantee that, by the age of, let's say, 18, all persons can responsibly drive or vote and know enough to be self-sufficient. Real life obviously bears this out. However, those (and other) laws do exist and, hopefully, will continue to exist. Laws don't exist simply to punish people. They act as goals, expectations, etc for both the individual and society as a whole. I think it can be said that laws are abstract, and as such, they don't always jive with reality. Due to this quality (of being abstract), laws are subject to great debate. Perhaps the intent of a law (any law) should be questioned. Here, for example, one could ask about the legislative intent of laws allowing age 13 children to lawfully engage in sex. Certainly not to allow age 13 girls to get pregnant. So, if not, then what other laws exist to prevent this from happening? But some people say that laws can't prevent it. From another perspective, we all know that many children and people push the limits, so if the law sets age of consent at 18, then it's reasonable that many age 16 and 17 kids will want to try it. If we set age 16 as the limit, we know that many age 14 and 15 kids will want to try it. So what are we saying about the age 14 limit? Certainly for most kids, they become aware of sex around ages 10 through 12 or even earlier. Where do we draw the line? Menstruation? Then the laws are merely saying that, if she's old enough to bleed, she's old enough to "breed"? Then we're going back to the ability to get pregnant.

So, getting back to those low-age-of-consent middle schoolers in Europe, where is the concern that girls will become baby factories and ruin their opportunity for a decent education and career? Doesn't this sort of thing seriously impede the progress of women's girl's rights?

No. Joseph was accused of attempting to seduce Potiphar's wife, but he didn't accuse her of anything or mention anything about clothes.

I'm surprised they haven't gotten rid of that yet as well [as religious marriages]. It's getting to where you can't even say the word God anywhere public these days. I wouldn't call that a ceremony any more than swearing an oath to tell truth in a court of law would be. I've been a Christian for 25 years, and the Bible does not claim Adam and Eve's marriage as a religious ceremony. I'm tired of hearing well-intended people claim that "you can't even say the word God anywhere public these days". It simply isn't true. Lastly, they got rid of swearing on Bibles in courts where I am, and according to the Bible, it's evil.

The line of sight and the centerline of the bore are not parallel, but the muzzle is tilted slightly upward to compensate for gravity. Turning the gun 90° onto its side does two things: it causes the bullet to begin dropping away from the line of sight immediately, and it causes the bullet to veer to the side. With practice, a shooter can compensate for this different kind of orientation. I saw a video years ago of an FBI agent who could shoot his pistol at all orientations (and hit the target): standard, on its left side, one its right side and even upside down. Of all places I could have seen this, it was a short clip on one of the original Mousketeers shows! As for shooting from the hip, it takes a little practice to, say, kick a can around at 25 feet. If you're indoors, you would probably hit an intruder from the hip without any practice, seeing as how people are so big and indoor distances don't go much beyond 15 feet or so. That's why, in clearing a house, it's preferred to hold the gun close to your body, instead of with arms fully extended (as we often see in movies). You don't want the gun to "announce" you entering a room, and you don't want the intruder the opportunity to take the gun, or disable it, or injure your arms. You want it just enough in front of you to shoot to either side (or to turn around quickly) as shown below.

Sammy got it!

I found this:

Interesting. I made a polygon perimeter method to compare to my polygon area method in post #59, and it's estimations using n-gons equal the area estimations using 2n-gons.

Use base 27 or 54 (or other) for the most efficient use of numbers with the first letter of the word being the least significant "digit". So, in their order, the letters encode as 27º, 27¹, 27², 27³, etc. That is, "a..." = 1, "b..." = 2, etc, "y..." = 25, and "z..." = 26; and ".a.." = 27, ".b.." = 54, etc; "..a." = 729, "..b." = 1458, etc.

Perhaps septic shock and diarrhea are symptoms of an infection.

So, trimethylxanthine is the only stimulant in the bunch?

I don't see the following formula among the posts here: π ~ n∙sin(360/n)/2 as n → ∞ (start with 4 and go by factors of 2). This method uses regular polygons inscribed within a circle. It starts with an inscribed square, then an octagon, 16-gon, 32-gon, etc. It's interesting to note that each new n reduces the error by about 25%. This means that each reiteration adds to the approximation about ¾ of the segment between the chord and the arc.

Try tea. Although scientists say that coffee and tea contain "caffeine", the two drinks don't contain the same chemical. Generally, the caffeines are methylated xanthines — coffee contains 1,3,7-trimethylxanthine, and tea contains 1,3-dimethylxanthine. Most of coffee's "caffeine" utilizes the paraxanthine metabolic pathway, while tea's "caffeine" utilizes its own metabolic pathway. I have found this site very informative.

The hydrogen bonds help keep the stream consolidated as it accelerates, and the moving stream does produce a "parasitic drag", which would hold the stream back, but it is a relatively minor force.

Constipation.

The word routinely got me thinking. Some people have a low threshold for sex; whereas, if a person requires a well-examined, well-defined, well-accepted, stable, committed relationship before sex, then it's a rather high threshold. And then there's trying out sex during the engagement, which is technically pre-marital, but not "pre-committal". So, I'm thinking the more appropriate metric is the shades-of-gray "level of committal" rather than the black-and-white marital/pre-marital.

Keep going. I never thought of ml, but that's a good one. The factor of 1.85×10¹² is a clue of sorts because it's not an even power of 10.

One minor point I wish to harp on: It is no longer standard practice to using underlining in citations. It was a compromise when people used typewriters. Proofreaders underline the words they want to appear in italics, and then they write "ital" in the margin next to the words. Typewriters cannot italicize, so the compromise was to simply underline. As to the kinds of references, I suggest: Cite for a real reason, and not just to have citations. Use the most relevant citations. Use the most recent citations. Use citations from peer-reviewed publications. (And, just for fun, who would have thought that this paper would be the most highly cited paper in publishing history?!)

... and then you launched into your academic habits. So, why? Why does chemistry attract your attention? If it has already attracted you, and you are sure of it, then it has attracted you for some time now. Do you do chemistry experiments at home? Do you hang around with your chemistry teachers at school before/after classes? Bottom line — do you have a passion for it? Do you see it as your way of making the world a better place? High school is a time when teachers and parents need to be encouraging their students to realize what they have a passion for and how they want to make the world a better place. Unfortunately, little or none of this actually takes place, and students end up leaving high school on autopilot. As it is, we have far too many rock stars and video game beta testers.

Clue: It's near the middle of the alphabet.

Maybe the rope holding the basket broke. But seriously, OMG! Maybe she fell off the bed ... or the balcony. In an important way, virginity is not what you're giving someone, it's a sound precaution about what you're not giving someone. It must really suck to have to give up the fact that, for example, you have genital herpes, which means not even heavy petting during an outbreak (or even kissing if it has infected your mouth ) and that a woman's babies can become infected. And that's before marriage and even before things get serious. Not something you'd want to put in your online dating service description.

The ability to perceive, comprehend and manipulate abstract information. The ability to recognize cause-and-effect, correlation and relationships. The ability to see the signal through the noise.

Reasons to maintain virginity: No sexually transmitted diseases (Old joke: What do you give a woman who has everything? Penicillin.) Men will never wonder if they have a child somewhere. (My brother has wondered for 40 years.) Women will never wonder who the father is. (Very embarrassing to write "Unknown" on the birth certificate -- or if she's a slut, maybe it's a badge of honor.) Marriage means sharing, which is cute/romantic, but very few women want to share the expense of child support payments for another woman's brat. ("No kids, we can't go to Disneyworld because we had other expenses to pay.") No emotional attachments outside the marriage (once you get married). Nothing to compare your partner to. No second-guessing your choice of marriage/sex partner. Virgin marriages: I don't know if they last longer. As much sex as possible: Remember trying to eat all that Halloween candy in one night? You get sick of it after a while. If you're a nice guy (and I think you are), it'll probably hurt you emotionally. You'd need to learn to treat women as sex objects, and you'll likely end up with women who treat men as sex objects. The ultimate marriage gift (pick one): Virginity A sexually-transmitted disease A stepchild/children/child support payments Other Pain from a popped cherry: Many/most women are so physically active now that there's probably not much damage/pain. Lots of blood: Never. We're talking about a small bandaid kind of bleeding, not her menstrual flow. Dying from sex: Never. She's more likely to die rofl about such an idea. How to spot male virgins: Nervous, confused, fumbling around, don't know what they're doing, etc. But another virgin might find this reassuring. Personal accounts: ? Seeking guidance: The questions you ask here show that you're fairly naive/innocent, which isn't a bad thing in itself, but it means to me that you'll probably encounter some disaster by trying to get laid, especially trying to get laid as much as possible. Losing one's virginity reminds me of getting married. I've known several people who married for the first time late in life (40+), and all of them were so happily married that they never had regrets (ie, they never said anything like, "I should have married earlier in life"). Ignore anyone who says that if you haven't kissed/fooled around/gotten laid/etc by now, that you're a loser and/or you'll never get anything this late in life. You're living your life, not theirs. Looking for sex with raging youthful hormones is like food shopping when you're starving to death. A wise man once told me: When the marriage is healthy, sex is only 10% of the reason, but when a marriage is in trouble, not having sex is 90% of the problem.