What Happens If a 1k Resistor Is Connected Across an LED?

If the LED has an external ballast resistor it will dim because the ballasted current is divided between the LED and the parallel resistor. You may not notice the change.If the extra resistor drops the voltage across the LED to less than its forward voltage the LED will go out.The best way to dim an LED is to increase the series resistance, this is energy efficient. If you are experimenting with LEDs try to limit the current to less than 20mA. They will light with very much less. Also, do not stress their reverse voltage characterists with AC. They are likely to be destroyed. An anti-parallel (silicon) diode will provide protection.

EDIT... Do take the trouble to view the comments on this answer. Even more enlightening... (and typos corrected)

• Related Questions

Since we only have two parties (those that matter), obviously it has to alternate between them, because there is no other way.Since 1950s this is how things have fared.Harry Truman -- Democrat - 8 yearsDwight Eisenhower - Republican - 8 yearJohn F. Kennedy Democrat - 4 yearsLyndon Johnson Democrat - 4 yearsRichard Nixon Republican - 4 yearsGerald Ford - Republican - 4 yearsJimmy Carter - Democrat - 4 yearsRonald Reagan - Republican - 8 yearsGeorge H.W. Bush Republican - 4 yearsBill Clinton - Democrat - 8 yearsGeorge W. Bush Republican - 8 yearsBarack Obama -- Democrat - 8 years(Years rounded to the nearest term limit)The reason for the same party to not win continuously is because even if the ruling party did a lot of good things, there will always be things that they promised but couldnt get done for various reasons like lack of a proper plan, lack of Congressional support etc,. That might lead to people losing trust in a particular party.Also something were to happen during the rule of one party even if it is something they have no control over, the other party would be quick to point out that as a mistake and that might turn some people towards the opposition and can help them win the next election and this cycle continues

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Why do we use 50 hz frequency?

Because its a standardized frequencies.The choice of line frequency is a compromise of various technical constraints. The determination took place in the early days of electrification, ie at the turn of the century between the 19th and the 20th century. The relevant boundary conditions were therefore those that emerged at that time. Here are some of them:Lamps flicker when powered by AC less than 42Higher frequencies allow smaller transformer cores to be used. The transformers are thereby smaller, lighter and cheaper at the same power.Higher frequencies produce greater losses in lines due to the skin effect. As a result, the maximum economic thickness of a pipe is determined in practice.The network frequency in a network system must be the same and synchronized everywhere.Higher frequencies correspond to shorter wavelengths. In spatially widely distributed network systems, this makes phase shifts more noticeable, which makes synchronization more difficult.The grid frequency is directly related to the speed and number of poles of generators and motors. Increasing the frequency requires either an increase in the speed (possible problems with centrifugal or centripetal forces and / or bearings) or an increase in the number of poles (greater technical complexity and thus higher costs).

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If all ants worked together to kill humans, could they wipe us out?

It would be close, but id say they probably could.First off, there are literall trillions of ants that range from the little lemon ants to the larger and horrifically painful bullet ant. Included are the infamous fire ants and the annoying carpenter ants. All together there are an impressive number of skills present in the ant family.Just imagine: no conventional weapon would work against them (you can't shoot, stab, etc. an ant), carpenter ants would be able to destroy most of the worlds buildings, it would be almost impossible to keep a building clear of them because they are so small, it would be incredibly hard to sleep if ants were constantly working their hardest to march up your nose, ears, mouth, etc.

, swarms of them could destroy crops if they worked hard enough, fire ants could make any stretch of ground a living hell, and poisons on such a large scale to combat them would probably do just as much harm as good. It would be catastrophic.Unless humanity found a way to live on the water and keep ants from making their way into our ships, we would probably be exterminated (pun intended). At the very least, life would become many degrees more miserable.

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What will you do when you cannot trust your government?

Lots of people here using this question to express how they never, never, ever, never trust governments and politicians.Which I suspect is what the questioner wished to provoke.Thing is its unreasonable to expect that you could form a government entirely composed of totally trustworthy saints. There just arent that many of them and they often dont want to go into politics or the civil service.But you can construct social structures that are reasonably trustworthy though composed of less than perfect human beings.Which is why I find the politicians always lie and government is the enemy ideas that you get on Quora too often to be glib, facile, lazy and dumb.

That said, assuming I found that my government was untrustworthy enough for me to care what could I do.In descending order of difficulty:Create a reform movement and transform our govenrment without the use of violence.Start a revolution and transform our government with the judicious use of violence.

Emigrate to somewhere more agreeable to me.Withdraw from public life and keep my head down.Im sixty five. A quiet life looks good at my age and in my state of health.

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What was the meaning of the song "Stairway to Heaven" to you when you were a teenager? What did you feel was the message of the song?

I was a teenager right at the height of Led Zeppelins fame.I never once contemplated the words to Stairway. I dont recall any conversation with a fellow teenager where the lyrics were discussed. I believe there was general acknowledgment that the words had no great meaning.Stairway was all about Jimmy Pages guitar playing. My cousin showed me how to play the intro to Stairway while sitting around in his basement on a lazy summer day. That Seventies Show is a spot-on portrayal of hanging out in basements in the Seventies. And the No Stairway scene in Waynes World is a spot-on portrayal of Seventies teenage musicianship: every teenage boy who got their hands on a guitar (and many of the girls, too) could play Stairway. Still, a lot of them wouldnt consider it Zeppelins best song.

Zeppelin was a kick-ass rock band, but I was never a fan of Robert Plants helium-voiced singing nor his babbling Tolkien-inspired lyrics. I grew tired of hearing Zeppelin over and over on the radio, and was thrilled when punk and New Wave came along in the Eighties

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Was Churchill's order for the British Royal Navy to attack the French Fleet at Mers-el-Kébir (3 July 1940) justified during WW2?

Such questions are often presented and answered:Without full knowledge of the historical situation.Through the lens of modern morals and sensibilities.With hindsight based on knowing what happened as a result of the order, and what happened during the rest of the war.

So it shouldnt need to be said, but I will, that the decision was far more complex than simply knowing what the order was and what resulted from it. Therefore please read these answers with that in mind and understand that Britains situation in July 1940 appeared to be extremely fragile facing an all-conquering Germany (which remember at the time had signed a pact with the Soviet Union as well). Nobody could be sure about what the French would do with this fleet - and being sure is the only thing that mattered. Nobody knew that the US would join the war later, or how much lend lease could be arranged. And you can be sure that Churchill wouldnt care what people thought of him over 75 years later when his greatest concern was getting Britain through one year, let alone three quarters of a century.So basically the decision was completely justified.

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To force Japan to surrender during WWII, were any options considered other than blockade, nuclear weapons, and invasion?

This type revisionist history question has been beaten to death here on Quora. The atomic bombings ended the war which was costing a large number of lives daily in nine (9) days. POWs who were intended to be killed before surrender were freed and this long war was truly over. The only other serious option was invasion. There already had been firebombing of cities to destroy war material manufacturing since Japanese manufacturing relied on many small nearly home-based industries which were situated all over cities. This was even resumed for one day after a pause after the 2nd bomb had been dropped on Nagasaki because there had been no Japanese reply accepting the terms of the Potsdam Declaration. There already was a submarine blockade sinking ships bringing materials and foodstuffs to Japan from China, Korea, Manchuria and other still conquered territories. There was an attempted military coup that killed the senior general officer within the Imperial compound to prevent the Emperor's surrender edict to be broadcast the night before the surrender. The atomic bombings saved millions of lives by ending the war. Japan became a prosperous nation after that. Hiroshima and Nagasaki both quickly resumed being habited cities and today are flourishing. What more do you want?

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What is driving the campaign against Dominic Cummings in the UK? Is it zeal for obedience to laws and regulations, personal hatred because he works for Boris Johnson, a desire to overturn Brexit by any means, or something else entirely?

It is a desire for consistency.Everyone else in senior positions in the government, especially positions pertaining to the pandemic, has resigned after having been found to make trips, often for trips of much shorter length than this. There have been people resigning who haven't even made such trips but were the destination for others travel.They didnt snivel and make excuses.The concern is that we might continue to the path of erosion of standards in public life. There is concern that those who make the rules may become arrogant and think they can get away with such things.There is concern that in some circles in government, loyalty is a substitute for integrity. To many there is a desire to have this belief repudiated and that no one, no matter who their friends are, be exempt from government policy.

There are some that are concerned that this represents an unequal application of law and that there should be consequences for everyone who lets down the country by their failure to adhere to the same high standards of behaviour that almost everyone else is adhering to.There is a concern that power corrupts and a desire to limit the spread of such corruption