Any coin can penetrate glass!!!

A random drinking glass, a borrowed cloth and a borrowed coin are the actors in this "physical" proof:

The cloth is spread over the glass and held together at the bottom. In your other hand, hold the coin.

Suddenly, you hit the coin against the side of the glass. You hear the impact. — And immediately afterward, the coin lands on the bottom of the glass. — A penetration of fabric and glass! —
They remove the cloth and hand the glass to the spectator, who can now take out his or her own coin.

You will receive a small, clever tool and an illustrated explanation.