Question

two cubes of ice are pressed hard

Answer 1

This is a process known as regelation.

Regelation is the phenomenon of melting under pressure and freezing again when the pressure is reduced is the phenomenon of melting under pressure and freezing again when the pressure is reduced.

Regelation occurs only for substances, such as ice, that have the property of expanding upon freezing, for the melting points of those substances decrease with the increasing external pressure. The melting point of ice falls by 0.0072 °C for each additional atm of pressure applied. For example, a pressure of 500 atmospheres is needed for ice to melt at −4 °C.

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Answer 2

Que: What is the full form of SONAR.

Ans: Sound Navigation And Ranging.