rewrite this: Imagine a machine with two coils of wire wrapped around a metal core. Electricity flows into one coil (the primary), creating a magnetic field around the core. This magnetic field is like an invisible bridge between the coils. The cool thing is, this magnetic field can create electricity in the other coil (the secondary). By changing the number of windings in each coil, we can control the voltage of the electricity coming out. This is how a transformer acts like a voltage changer for AC electricity, making it higher or lower. Transformers are also handy because they keep the electricity in the two coils separate, like having two lanes of traffic that never touch. They can even change how electricity "resists" flowing (impedance) and are used in many ways to make electrical systems work better