Security card continued

Obtain a thick piece of cardboard. Cut a rectangular hole so that the match box fits exactly into it.
The picture on the right shows the other end of the cardboard. The key card mechanism is now firmly secure.

Draw a circuit diagram of the key card mechanism.

Explain what is meant by an open and closed circuits.
Explain how the key card completes the circuit when inserted into the slot.
How have you protected the key card from forgery ?
It should be possible to bypass the security key if a solid piece of metal is inserted into the slot. Explain how a short circuit can be used to overcome this fault.