the citadel or high fortified area of an ancient Greek city. the Acropolis, the citadel of Athens and the site of the Parthenon.
Electromagnets are used in a number of everyday devices. One useful characteristic of an electromagnet is the fact that you can vary its magnetic force by changing the amount and direction of the current going through the coils or windings around it.ummary. Electromagnets are used in a number of devices, such as loudspeakers and tape recorders. Some electromagnets can be very strong and its power can be readily turned off and on, such as in junk yard electromagnets and electromagnetic locks.
Method 1 of 3: Make a Simple Electromagnet. 1. Get magnet supplies. To make an electromagnet, an electric current is run through a piece of metal, which creates a magnetic field. To make a simple electromagnet, then, you'll need a source of electricity, a conductor, and metal.ethod 1 of 3: Make a Simple Electromagnet. 1. Get magnet supplies. To make an electromagnet, an electric current is run through a piece of metal, which creates a magnetic field. To make a simple electromagnet, then, you'll need a source of electricity, a conductor, and metal.