PROJECT # 2
To use your electromagnet to move a plunger, and to apply this
as a doorbell chime and a launcher (electrical catapult).
MATERIALS NEEDED: wood from project 1
From project 1 you found out that electromagnets are stronger when they have iron core in them, but it is also interesting to note that a coil with a core partially inserted will actually pull the core in when electricity is applied.
Door Chime Model
Remove all the wires from your wood. Connect one end of the strong electromagnet to hole 1. Take two battery holders one negative side of a battery connect it to the key switch, the positive side of the same battery connect it to the negative side of the other battery, then the positive side that is left connect it to the other end of the electromagnet. Place the nail inside the straw in a way that only 1\2'' of the nail is inside. Press the key. What happen? At this point you can do many things with your electromagnetic, but we will concentrate only on two applications. Now that the nail is inside the straw take a spoon and tie a piece of string on the spoon's tail and hang it in a way so that the spoon is hanging close to the electromagnet from the pointing side of the nail. Press the key switch. What happen?
Electric CatapultTake your wood and don't remove anything. Take your electromagnet and hold it at the edge of the table pointing horizontally. Pull the nail back and insert a small pebble or another small object if pebble is not available. Just be careful not to aim this at anyone, and then press the key. Make more tries on different angles and see at what angle does it gives you maximum launching distance.