For whom is the empty grave near the tomb of the Prophet Muhammad reserved? Detailed answer

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For whom is the empty grave near the tomb of the Prophet Muhammad reserved? Detailed answer

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For whom is the empty grave near the tomb of the Prophet Muhammad reserved?

The Masjid al-Nabawi mosque in Medina has a separate Green House, inside which is the tomb of the Prophet Muhammad. Next to it are buried the first two caliphs, Abu Bakr and Umar, and on the other side there is another empty grave. Many Muslims and Quran commentators believe that it is reserved for Jesus, who will return to Earth to kill the Antichrist and then reign for 40 years.

Authors: Jimmy Wales, Larry Sanger

Random interesting fact from the Great Encyclopedia:

Who Invented the Refrigerator?

Freezing is the process of creating cold and keeping things cold. This is achieved by completely extracting heat from objects, so freezing is the process of removing heat. In ancient times, of course, snow and ice were used for this purpose. It was the natural way. This is how the wines cooled.

But even in ancient times, another way of creating cold was known. It was the process of dissolving certain salts in water. Materials such as saltpeter salts and ammonium nitrate cool the water in which they dissolve. Thus, the temperature of the water drops. Salt lowers the freezing point of water. When salt is poured onto ice, it turns into water. For this change to occur, energy costs, and hence heat, are needed.

Thus, the primary methods of cooling were natural, such as ice and water and salts dissolved in water. But there is another way of freezing, it is called evaporation, the transformation of a liquid into vapor. When a small amount of water or alcohol gets on the hand, a cooling sensation is felt: the liquid evaporates, taking away part of the heat. This principle of evaporation is used in modern refrigerators.

In 1823, Michael Faraday discovered how ammonia vapor is turned into a liquid by increasing pressure and compressing it, and then extracting heat. When the pressure increases and the liquid evaporates again, this requires heat, and cold is generated.

How did this discovery make the invention of the refrigerator possible? Everything is very simple. There was a way when first the vapor turns into a liquid - giving off heat. Then we can turn it into steam again - taking away the heat. By controlling this process, making it continuous, we get modern refrigerators.

The first refrigerators based on this principle were built by the Swiss inventor Carl Lind in 1874 to cool beer. In 1877, Lind used ammonia as a liquid in his invention, hence the history of the refrigerator.

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