Why hot water can freeze faster than cold water?"MPEMBA EFFECT"

The Mpemba effect is a process in which hot water can freeze faster than cold water. The phenomenon is temperature-dependent. There is disagreement about the parameters required to produce the effect and about its theoretical basis.

However, even with this definition it is not clear whether "freezing" refers to the point at which water forms a visible surface layer of ice; the point at which the entire volume of water becomes a solid block of ice; or when the water reaches 0 °C (32 °F). A quantity of water can be at 0 °C (32 °F) and not be ice; after enough heat has been removed to reach 0 °C (32 °F) more heat must be removed before the water changes to solid state (ice), so water can be liquid or solid at 0 °C (32 °F).

With the above definition there are simple ways in which the effect might be observed. For example, if the hotter temperature melts the frost on a cooling surface and thus increases the thermal conductivity between the cooling surface and the water container. On the other hand, there may be many circumstances in which the effect is not observed.

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Why do the Indian telecom operators offer their services with 28 days validity, not 30 days?😡😡

Here telecom operator are very clever, b ecause telecom operators want to earn money of 13 months instead of 12 months. Let do the calculation and find out why telecom operators are offering 28 days validity. Each month they get 2 days more, therefore in a year they get additional 24 days. There are 7 month which has 31 days so they get additional 7 days.Now in case of February ,it has only 28 days not 30. So the total number of days they get are=24+7-2=29 days. So if you recharge 12 times then more 29 days are left in a year.🤔🤔 Means for another 29 days you have to recharge from that telecom operator.😫😫 So you have to recharge 13 times in a year instead of 12 times in a year. So telecom operators provide 28 days validity only. First one telecom operator started and then another telecom operators also understood this concept and they also applied 28 days validity both in data packs and voice packs.😱😱😱

What is the best way to set up the information to be transmitted to give the maximum information transfer across a given channel?

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