A rectangular loop near wire emf refers to a circuit configuration where a rectangular loop of wire is placed near a straight wire, resulting in an induced electromagnetic field (emf) in the loop.
When a current flows through the straight wire, it creates a changing magnetic field around it. This changing magnetic field induces an emf in the rectangular loop, causing a current to flow through the loop.
The emf induced in the loop is directly proportional to the rate of change of the current in the straight wire. This means that the stronger the current in the wire, the stronger the induced emf in the loop.
The magnitude of the induced emf in the loop depends on the strength of the current in the straight wire, the distance between the wire and the loop, and the size and shape of the loop.
This phenomenon is used in devices such as transformers, generators, and electric motors. It is also used in wireless charging technology, where a charging pad induces an emf in a device's loop antenna to charge its battery.