Question

The diagram given below shows a copper wire wound around a U-shaped soft iron bar. An iron pin is brought near the arrangement. First Source P and then Source Q are connected across AB, each operating independently.

(a) State true or false:

Source P as well as Source Q, when connected across AB, can attract the iron pin.

(b) Justify your answer to (a) with a suitable reason.

Answer 1

(a) This statement is true.

Explanation:

Both Source P (likely a battery/DC source) and Source Q (likely AC or another DC source) can create a magnetic field when connected, turning the coil into an electromagnet, which attracts unmagnetized soft iron pins, as iron is always attracted to magnets.

(b) An electric current (from any source) flowing through a coil creates a magnetic field; when this coil is wound around a soft iron core (forming an electromagnet), it becomes a magnet itself and attracts ferromagnetic materials like iron pins, with the attraction happening regardless of the source type as long as current flows.