Question

when the card is flicked with the finger the coin placed over it fall in the tumbler.Why??
plzzz give me this answer I urgent......

Answer 1

the case of the Coin Drop activity, the penny is at rest sitting on top of the card. Watch it as long as you like but, on it’s own, the penny will not move from that spot. When you flick the card out from under the penny, you allow gravity (an outside force) to act on it and drop it into the glass. The bottom of the glass stops the penny from falling. However, if the penny were a lot heavier (had more mass) and were falling much faster, it could go right through the glass (and probably the table supporting it, too).

So, why doesn’t the penny take off when the card is flicked? If you flick the card correctly, it simply slides out from between the glass and the penny. There’s not enough friction from the card to take the penny with it.

Answer 2

Read this...
There is your answer.
Hope it helps you.