what is voltage

Current is like speed of water flow and voltage is like height of water fall.
A step-up transformer increases the 'electrical height' and the opposite happens in 'step down'. The way this is done is by changing the ratio of coils of wire between input and output circuits. The process relies on electromagnetic induction between the coils which are part of separate circuits.

Vik,, some define voltage as "electrical pressure"

There are two windings on a magnetic core (iron, steel or something mag, usu in layers). To the primary you connect to a varying voltage. The fluctuating field then induces a voltage in the secondary with the same waveform but without dc component, at a voltage determined by winding ratio

As I recall the layers are insulated to prevent significant current flow. You could probly find a more satisfactory explanation using Google

According to google - Voltage is an electromotive force.



A transformer is made from two or more coils of insulated wire wound around a core made of iron. When voltage is applied to one coil (frequently called the primary or input) it magnetizes the iron core, which induces a voltage in the other coil, (frequently called the secondary or output). The turns ratio of the two sets of windings determines the amount of voltage transformation.

With a step up transformer or step down transformer the voltage ratio between primary and secondary will mirror the "turns ratio" (except for single phase smaller than 1 kva which have compensated secondaries). A practical application of this 2 to 1 turns ratio would be a 480 to 240 voltage step down.

Voltage is the difference in charge between two points. Voltage is also known as electromotive force. This is a quantitative expression of the potential difference in charge between two points. Voltage is symbolized by an italic letter V or E. Voltage can be direct or alternating.

Not sure Ruby that's quite accurate. Doesn't "magnetized" usu mean a perm or semi- state

Think of a water tower. The water in the tower, combined with its height, is voltage. This flows down through a pipe with a valve that restricts its boundless flow out of the tower, if the bottom fell out. Consider the valve as resistance. The more you open the valve, the less resistance to the water flowing through the pipe. The actual flow of water through the pipe is current. And you can relate that to the current of water flowing in a river. So, all of this upholds the concept of Ohms law. The voltage, divided by the resistance, equals the current flow. Again, reduce the resistance, the more current flows. And, like a battery, as the water level decreases in the water tower, the less push it has to push the water out of the pipe, and the voltage decreases.

It's all physics and there are many other corollaries. This one has been used for years to teach students. The ones provided by others regarding voltage step-up and step-down are reasonable.
JByers - 40 years in Electronics Engineering.

....as stated above weeks ago !

Flow of electrons is a very basic idea of visualizing electricity. It is not flow of electrons in actual sense, it is flow of energy. In a transformer, when primary winding is given electricity supply, magenetic field is formed which when it is alternating current, generates mutual induction into the secondary winding. Now when load is connected to secondary winding, energy flows from primary to secondary driving the load. Actually it is very complicated and needs indepth understanding of how energy transferred.

Voltage is the potential energy that makes the electrical current flow in the circuit by pushing the electrons around. Voltage also called electromotive force. The quantity of charge carriers that pass a fixed point per unit of time.