Photo 1: As seen in the photos, there are linkages in the study lamp. This allows the lamp to be turned to shine at almost all areas of the table.
Photo 2: Same as Photo 1
Photo 3: The mechanism used in the scissors, where it is a first class lever.
At certain households, people use a piece of sloping rubber as a door stopper. There are many problems with this rubber piece. Firstly, if one doesn't use enough force to stick the rubber under the door, the piece of rubber will not work properly as a door stopper. Also, if too much force is used, the rubber may also break and it will no longer be able to function as a door stopper. My suggested solution is to attach magnets to both the wall and the door such that when the magnet on the door and the magnet on the wall are attached, it will take some effort to pull it apart again. (Photo 4)