The Coin Drop experiment is a classic experiment used to demonstrate Newton's First Law of Motion. In this experiment, a glass is covered with a card and a coin is place on the card. The card is given a quick strike and the coin falls in the glass. (YouTube Demonstration).
Should the coin be heavier or lighter in this experiment?
The following two statements give contradictory conclusions:
If the coin is heavier it means it has greater inertia. So it wishes to remain in its state of rest compared to a lighter coin. So, a heavier coin will fall vertically down.
If the coin is heavier, the normal contact force between it and the card is large compared to that in case of a lighter coin. So, the friction between a heavier coin will and the card will be higher than a lighter coin and the card. So, using a heavier coin will make the coin travel along with the card, instead of falling vertically down.
It can be seen the factors contributing to inertia and friction give contradictory conclusions. So, does the mass of the coin used in the experiment affect the quality of the final result, or it doesn't matter? If mass matters, why is one factor out of inertia and friction is chosen over the other? Or does it depend upon which of the above two factors dominate and vary from one experiment to another, or while using pair of surfaces of different coefficients of friction?