6B:
Define “Alternating current.”
AC electricity refers to when there is a periodically changing direction of current and voltage.
6B:
Define “Root-mean-square.”
A DC current or voltage that’ll produce the same average power as a source of AC electricity.
6B:
Define the term “Peak Value.”
The maximum value of current or voltage supplied by an AC source. This is found via the amplitude of an AC voltage or current graph.
6B:
Define a “Transformer.”
A Transformer uses electromagnetic induction to transfer power from one circuit to another via the following process.
Two coils of wire (primary and secondary) are wrapped around an iron core. An AC power source supplies an alternating current to the primary coil of wire, producing a changing magnetic field that is guided by the iron core through the secondary coil of wire. Given there is a changing magnetic field through the secondary coil of wire, an EMF is produced induced which induces a current to flow in this wire. As the raito of the number of turns of wire in each coil is proportional to the ratio of the voltages produced in each wire coil, voltage can be stepped up or steped down (vice versa for current).
6B:
Distinguish between a “Step-up,” transformer and a “Step-down,” transformer.
A step-up transformer steps up the voltage in the secondary coil of wire and steps down the current. In contrast, a step-down transformer steps down the voltage in the secondary coil and steps up the current.
6B:
How does the use of Transformers reduce power loss in transmission lines?
An AC power source is connected to the primary coil of a step-up trasnfomrer. This increases the voktage supoply to the secondary coil (which is attahced to the transmission lines) and reduces the current in the transimssion lines. Thuis in turn reduces the voltage drop and power loss in the trnamision lines .
