Video Transcript
Which of the following is a
suitable material for the core of a transformer? (A) Copper, (B) aluminium, (C)
polypropylene plastic, (D) iron, or (E) carbon.
To answer this question, let’s
first remember that a transformer consists of two solenoids that are linked by a
common core. The purpose of this core is to
redirect the magnetic fields to the solenoids and allow a more efficient transfer of
energy from one coil to the other. So, if this core is supposed to
redirect magnetic fields, it makes sense that it needs to be made from a
magnetizable substance. If it wasn’t made from a
magnetizable material, it wouldn’t do anything to affect the magnetic fields of the
solenoids.
So, to answer this question, we
simply need to identify which of the materials we’re given is a magnetizable
substance. First, we can recall that only
certain metals are magnetizable. So, we can rule out any nonmetallic
materials straightaway. This means we can rule out
polypropylene, a kind of plastic, and also carbon, which is not a metal. This leaves us with copper,
aluminium, and iron, all of which are metals.
However, not all metals are
magnetizable. Of these three, only iron is
actually magnetic. The other two are not
magnetizable. So, we can eliminate these options
as well.
This leaves us with only one
option, iron. Iron is a magnetizable metal and is
a common material for use in transformers. So, the correct answer to this
question is option (D). Iron is a suitable material for the
core of a transformer.