Question

why do two pieces of ice join when they are pressed together

Answer 1

When they are pressed together little heat is generated due to pressure and of friction, which just melts the outer layers , when that is melted friction decreases and due to the low temp of both the ice cube the water just refreezes .

Answer 2

This occurs due to revelation.

This is the phenomenon of ice turning into water when pressure is applied and then reconverting into ice when pressure is removed.

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