how to make road rail signal using electromagnet
Not generally, although MacGuyver could make an electromagnet with a toothpick and a spool of wire.
To chew on it.
An electrical current will cause an electromagnet to energise.
It needs more than an electromagnet. You have an electromagnet with an iron diaphragm in the magnetic field. When the audio current from the amp flows in the electromagnet, the diaphragm moves at the same frequency, making the sound that you hear.
You could either put a bar of iron in the center of the electromagnet, increase the voltage that you put in, or make more loops of wire.
Electrical to Mechanical
The wire in a electromagnet is the conductive property transferring power. The thicker the wire the more power transferred to the electromagnet for a exponential amount of power.
Yes, if you increase the number of coils or loops in an electromagnet, it's power increases.
reducing the number of coils around the core or by reducing the current in an electromagnet, will cause the magnetic power to weaken.
For a simple copper wire around iron nail electromagnet, increasing the number of rounds the copper wire makes around the nail will increase the electromagnet's strength. Also, increasing the voltage applied(adding a battery) will increase the magnetic field.
Adding more turns of wire to the electromagnet will make it stronger without changing the applied voltage.