James

Hello. I am working on a project and need your help!

I need a device that pulses for 15 seconds and rests for 900 seconds (15 minutes). I know the formula for a 555 timer in a-stable configuration as follows: High state = .7 (R1 + R2) C, where R1=2.2Kohms, R2=127Kohms, and C=.01F (10K micro ferrads). R1 should = 2.2Kohms. R2 should = 127Kohms. C should = 10KuF or .01F.

Here is the mystery: Using a 9V battery (9.27V on Fluke meter), on a Radio Shack standard bread board, with the following a-stable configuration:\

pin 1 to ground

pin 2 to pin 6

pin 3 to LED, LED to resistor, resistor to ground

pin 4 to plus

pin 5 empty

pin 6 connected to pin 7 with R2

pin 7 connected to plus with R1

pin 8 to plus

C1 positive to pin 2, negative to ground

Should be fine, right? problem is, High state is approx. 26 minutes; Low state is approx. 19 minutes!

What is the problem?? Is it the constant? Help!

Thank you!!!

I am trying to build a control device for a sprinkler system that sprays water for 15 seconds, every 15 minutes. Apparently, 555 timers cannot maintain low state for 900 seconds (according to other answers). Is there any way to configure a 555 timer for this period? Should I use a counter instead with logic gates, etc? What is the best way to achieve these times?

Thank you!

I have tried to use online 555 calculators, but I have not found any that work properly for the following:

I need high state to be 15 seconds, and low state for 900 seconds (15 minutes). What must I use for R1, R2, and C1?

I know about the high and low-state formulas, but the answers are not coming out right. Perhaps I have the wrong units?

Thank you!

A co-worker uses so much perfume it smells like she bathes in it! It's so strong, it makes my eyes water from across the room! I tried going to my supervisor. I even talked to her about it. She still wears it. I have trouble concentrating when she is around with her overpowering scent. Please help! Thank you!

For example, if I am a passenger on a Delta Airlines flight across the United States, and I want to see what High-Altitude VOR's, NDB, DME, ILS, etc. the pilots are following, can I request that information (and actually receive it)?

Please provide some detailed instructions on how to completely annihilate those annoying little Easter marshmallow candies, the Peep.

I remember the story of the octopus in the Atlanta Aquarium years back named "James Bond." He could figure out novel situations quickly, such as how to open a mayonnaise jar to get a crab inside. But experts said his intelligence was very different from mammalian intelligence. In what way is it different?

And if octopuses are intelligent creatures, what does this mean for sushi eaters??!! ;)

Or do they? Seems to me that ice crystals would pierce the cell walls of the tree, thus killing it. So if they don't freeze, what keeps them from freezing?

Is there archaeological evidence that tells us how long ago it was when mankind first wondered at the origins and purpose of his existence?

The Mega Millions Lottery in the US has reached a record $540 Million.

If I win, maybe I will finally be able to afford health insurance!

What might be the reason for floating outside the body for a bit and watching below? Why don't we just go straight to the afterlife? Then, if we are revived, we could just return to our bodies. What's the "hovering" about?

Disclaimer: I am an atheist, formally a practicing Christian. I mean no disrespect by asking this question. I am only trying to stimulate intelligent discourse on the logic and the question of God's existence. If this offends you, please do not respond.

If God is not a narcissist, then why does God demand that we mere mortals worship him? This demand seems to be far more human than divine. For example, I know some surgeons who seem to think they are gods, and some seem to expect a certain amount of "worship". If we humans were made in the image of God, does that include personality traits such as narcissism? If this is true, is God then the ultimate narcissist?

A friend of mine is over 40 weeks pregnant and has been told she cannot be induced, due to a history of a C-section. I have not heard of this before. If this is true, what is the medical mechanism for this?

Do people rate answers based on the quality of the answer, or on whether they agree with the answer? Please explain your response. Thank you.

...to hurt Obama? The President's administration does not set gas prices, the companies that produce it do. Nor does he have a major impact on the price of oil; the World Crude Oil Market does (http://auto.howstuffworks.com/fuel-efficiency/fuel... (http://www.eia.gov/finance/markets/). Yet, he is continually blamed by his political opponents for the high gas prices. Simultaneously, he is accused of not doing anything to increase domestic fossil fuel production, when in fact he has done a great deal (including approved 485-mile southern leg of a pipeline from Oklahoma to the Gulf Coast, and approved dozens of other pipelines across the country; increased off-shore drilling while at the same time increasing safety; expanded on natural gas, solar, and wind power, etc.(http://www.nytimes.com/2012/03/23/us/politics/in-o... It seems awfully convenient for Obama's opponents that the gas prices are coincidentally sky-rocketing, and in a way that have experts baffled.

Please provide a substantive response. That is, please do not answer only with "yes" or "no", but rather please explain your response and support your conclusions. Thank you.

By "forever", I mean for the rest of your life. Please explain your answer. Thanks.

I read an NYT article not long ago about a scientific study which looked at IQ and conservative, right-wing Christian Republicans. Basically, it showed that such individuals tended to have low IQ's compared to the general population. (Sorry, I don't have the reference for that article; but I'm sure you can Google it).

What I'd like to see is a study about religion and IQ, not political affiliation and/or political spectrum and IQ.

Some of the smartest people I've known believe in God. On the other hand, it seems a large proportion of individuals with low IQ's tend to believe in God. My evidence, however, is anecdotal: I have encountered this apparent phenomenon while working in mental health for my state.

What do you think? Does belief in God (i.e., belief in a super-natural creator being) correlate with IQ? What would be even more interesting to me is to see if specific religious beliefs correlate with IQ (e.g., Hindus tend to be smarter than Christians, etc.)

I actually have three questions. Assuming reincarnation is real (if you don't believe in it, please don't respond):

Question 1: Are life forms reincarnated into more and more complex forms of life? For example, from an insect, to a fish, to a reptile, to a bird, to a mammal?

Question 2: Are humans the highest level of reincarnation, or might there be a more complex form of life?

Question 3: Is reincarnation limited to Earth life, or might a creature be reincarnated as a creature on another planet?

For example, English idioms such as "Take the bull by the horns", "The squeaky wheel gets the grease" and others, when literally translated into some languages, make little or no sense. So far, only humans can properly and reliably translate idioms. Another problem is that many idioms do not exist in other languages, or are in very different antithetical forms. For example, "The squeaky wheel gets the grease", in Chinese makes no sense. However, the antithesis does exist: "The nail that stands up gets hammered down". This idiom reflects the cultural value of community conforming, and valuing the group over the individual. A human would translate idioms that have no corresponding idiom by defining the meaning of the idiom in normal language, such as "When a person asserts himself, people tend to pay more attention to him." (i.e., "The squeaky wheel gets the grease.")

My question is essentially: Will computer technology ever be able to understand and translate idioms the way a human translator can?

Most of the dead were women and children. Here is the story from CNN: http://www.cnn.com/2012/03/12/world/asia/afghanist...

This is an experienced Staff Sargent, Special Forces with several tours in Iraq. This is his first tour in Afghanistan.

What would make a soldier do this? Do you think the psychological stress of multiple combat tours caused him to snap? If so, do you think his commanders share some of the blame for sending him (and thousands of other soldiers) on multiple combat tours?

I know this is a very sensitive issue for most. There are no right or wrong answers; but I'd like to know what you think. Please be respectful of others with differing views. Thank you.

By the way, I'm a veteran myself. I have my own opinion of what his reasons may have been. I'll add it later after a few responses.