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πŸ”— Two capacitor paradox

πŸ”— Electronics

The two capacitor paradox or capacitor paradox is a paradox, or counterintuitive thought experiment, in electric circuit theory. The thought experiment is usually described as follows: Two identical capacitors are connected in parallel with an open switch between them. One of the capacitors is charged with a voltage of V i {\displaystyle V_{i}} , the other is uncharged. When the switch is closed, some of the charge Q = C V i {\displaystyle Q=CV_{i}} on the first capacitor flows into the second, reducing the voltage on the first and increasing the voltage on the second. When a steady state is reached and the current goes to zero, the voltage on the two capacitors must be equal since they are connected together. Since they both have the same capacitance C {\displaystyle C} the charge will be divided equally between the capacitors so each capacitor will have a charge of Q 2 {\displaystyle {Q \over 2}} and a voltage of V f = Q 2 C = V i 2 {\displaystyle V_{f}={Q \over 2C}={V_{i} \over 2}} . At the beginning of the experiment the total initial energy W i {\displaystyle W_{i}} in the circuit is the energy stored in the charged capacitor:

W i = 1 2 C V i 2 {\displaystyle W_{i}={1 \over 2}CV_{i}^{2}} .

At the end of the experiment the final energy W f {\displaystyle W_{f}} is equal to the sum of the energy in the two capacitors

W f = 1 2 C V f 2 + 1 2 C V f 2 = C V f 2 = C ( V i 2 ) 2 = 1 4 C V i 2 = 1 2 W i {\displaystyle W_{f}={1 \over 2}CV_{f}^{2}+{1 \over 2}CV_{f}^{2}=CV_{f}^{2}=C({V_{i} \over 2})^{2}={1 \over 4}CV_{i}^{2}={1 \over 2}W_{i}}

Thus the final energy W f {\displaystyle W_{f}} is equal to half of the initial energy W i {\displaystyle W_{i}} . Where did the other half of the initial energy go?

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πŸ”— Founder's Syndrome

πŸ”— Business

Founder's syndrome (also founderitis) is the difficulty faced by organizations where one or more founders maintain disproportionate power and influence following the effective initial establishment of the project, leading to a wide range of problems for the organization. The passion and charisma of the founder(s), sources of the initial creativity and productivity of the organization, become limiting or destructive factors. The syndrome occurs in both non-profit and for-profit organizations. It may simply limit further growth and success of the project, or it may lead to bitter factionalism and divisions as the scale of demands made on the organization increases, or it may result in outright failure. There are ways in which a founder or organization can respond and grow beyond this situation.

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πŸ”— Pelorus Jack

πŸ”— Cetaceans πŸ”— New Zealand

Pelorus Jack (fl. 1888 – April 1912) was a Risso's dolphin that was famous for meeting and escorting ships through a stretch of water in Cook Strait, New Zealand, between 1888 and 1912. Pelorus Jack was usually spotted in Admiralty Bay between Cape Francis and Collinet Point, near French Pass, a notoriously dangerous channel used by ships travelling between Wellington and Nelson.

Pelorus Jack was shot at from a passing ship, and was later protected by a 1904 New Zealand law.

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πŸ”— Pantai Remis Landslide

πŸ”— Occupational Safety and Health πŸ”— Malaysia

The Pantai Remis landslide was a rock fall and flood that occurred on 21 October 1993, near Pantai Remis in Perak, Malaysia. The landslide took place in an abandoned open cast tin mine (in a region of the state well known for its tin mining industry) close to the Strait of Malacca. Video footage shows the rapid collapse of the working face closest the sea, allowing complete flooding of the mine and forming a new cove measuring approximately 0.5Β km2 (0.19Β sqΒ mi).

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πŸ”— The Great Plague of Marseille

πŸ”— France πŸ”— Death

The Great Plague of Marseille was the last major outbreak of bubonic plague in western Europe. Arriving in Marseille, France in 1720, the disease killed a total of 100,000 people: 50,000 in the city during the next two years and another 50,000 to the north in surrounding provinces and towns.

While economic activity took only a few years to recover, as trade expanded to the West Indies and Latin America, it was not until 1765 that the population returned to its pre-1720 level.

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πŸ”— Norton Commander

πŸ”— Computing πŸ”— Computing/Software

Norton Commander (NC) is a discontinued prototypical orthodox file manager (OFM), written by John Socha and released by Peter Norton Computing (later acquired in 1990 by the Symantec corporation). NC provides a text-based user interface for managing files on top of MS-DOS. It was officially produced between 1986 and 1998. The last MS-DOS version of Norton Commander, 5.51, was released on July 1, 1998.

A related product, Norton Desktop, a graphical shell for MS-DOS and Windows, succeeded Norton Commander. It came in two variants, Norton Desktop for DOS and Norton Desktop for Windows.

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πŸ”— McLibel Case

πŸ”— Law πŸ”— Freedom of speech

McDonald's Corporation v Steel & Morris [1997] EWHC QB 366, known as "the McLibel case", was an English lawsuit for libel filed by McDonald's Corporation against environmental activists Helen Steel and David Morris (often referred to as "The McLibel Two") over a factsheet critical of the company. Each of two hearings in English courts found some of the leaflet's contested claims to be libellous and others to be true.

The original case lasted nearly ten years which, according to the BBC, made it the longest-running libel case in English history. McDonald's announced it did not plan to collect the Β£40,000 it was awarded by the courts. Following the decision, the European Court of Human Rights (ECHR) ruled in Steel & Morris v United Kingdom the pair had been denied a fair trial, in breach of Article 6 of the European Convention on Human Rights (right to a fair trial) and their conduct should have been protected by Article 10 of the Convention, which protects the right to freedom of expression. The court awarded a judgement of Β£57,000 against the UK government. McDonald's itself was not involved in, or a party to, this action, as applications to the ECHR are independent cases filed against the relevant state.

Franny Armstrong and Ken Loach made a documentary film, McLibel, about the case.

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πŸ”— Polywater

πŸ”— Physics πŸ”— Skepticism

Polywater was a hypothesized polymerized form of water that was the subject of much scientific controversy during the late 1960s. By 1969 the popular press had taken notice and sparked fears of a "polywater gap" in the US.

Increased press attention also brought with it increased scientific attention, and as early as 1970 doubts about its authenticity were being circulated. By 1973 it was found to be illusory, being just water with any number of common organic compounds contaminating it.

Today, polywater is best known as an example of pathological science.

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πŸ”— Covid-19 Vaccine Candidates

πŸ”— Disaster management πŸ”— Medicine πŸ”— Viruses πŸ”— COVID-19 πŸ”— Medicine/Pulmonology πŸ”— Medicine/Emergency medicine and EMS

A COVID-19 vaccine is a hypothetical vaccine against coronavirus disease 2019 (COVID‑19). Although no vaccine has completed clinical trials, there are multiple attempts in progress to develop such a vaccine. In February 2020, the World Health Organization (WHO) said it did not expect a vaccine against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causative virus, to become available in less than 18 months. The Coalition for Epidemic Preparedness Innovations (CEPI) – which is organizing a US$2 billion worldwide fund for rapid investment and development of vaccine candidates – indicated in April that a vaccine may be available under emergency use protocols in less than 12 months or by early 2021. On 4Β May 2020, the WHO organized a telethon to raise US$8 billion from forty countries to support rapid development of vaccines to prevent COVID-19 infections, also announcing deployment of an international "Solidarity trial" for simultaneous evaluation of several vaccine candidates reaching Phase II-III clinical trials.

By May, 159 vaccine candidates were in development, with five having been initiated in PhaseΒ I–II safety and efficacy studies in human subjects, and seven in PhaseΒ I trials.

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πŸ”— Censorship by Google

πŸ”— Internet πŸ”— Law πŸ”— Freedom of speech πŸ”— Google

Google and its subsidiary companies, such as YouTube, have removed or omitted information from its services to comply with its company policies, legal demands, and government censorship laws. Google's censorship varies between countries and their regulations, and ranges from advertisements to speeches. Over the years, the search engine's censorship policies and targets have also differed, and have been the source of internet censorship debates.

Numerous governments have asked Google to censor what they publish. In 2012, Google ruled in favor of more than half of the requests they received via court orders and phone calls. This did not include China and Iran who had blocked their site entirely.

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