Buzzer production process is what kind of it?

1. Preparation of electromagnet M: about 6 cm long bolt on the wire about 100 laps wire, the wire end of 5 cm for the lead, with a transparent adhesive tape to the coil, so as not to release the coil, then tape it to the stick On a box, the electromagnet is done.

2. Preparation of shrapnel P: Cut a long iron sheet about 2 cm wide from the tin can box, bend it at a right angle, attach a lead of the electromagnet to the shrapnel, and then tape the shrapnel against the board.

3. With the paper to do the contact Q, with the bookclip pad high, with adhesive tape, leads to a wire, as shown in the diagram to connect the circuit.

4. Adjust the distance between M and P (by moving the box) so that the electromagnet can attract the shrapnel and adjust the distance between the contact and the shrapnel so that they can be touched exactly. After the power is turned on, the buzzer can be heard.