Class 12 Physics · Chapter 5 · NCERT (leph105)
See the tempting mistake students make in Magnetism and Matter, why it feels right at first glance, and a worked visual example that shows the right idea.
Wrong
Cutting a bar magnet in half gives one north pole and one south pole.
Why it feels right. The original poles are at opposite ends.
Right
Each ordinary fragment remains a dipole with its own north and south poles.
Worked example
As you work through Magnetism and Matter, listen for these everyday misunderstandings and use the prompt alongside each one.
If your child says… “Zero total flux means there’s no field.”
If your child says… “Twice as far means one-quarter of the field.”
If your child says… “Zero torque means it must be stable.”
If your child says… “I multiply moment by volume to get magnetisation.”
If your child says… “Relative permeability is just susceptibility.”
If your child says… “One pole repels it, so the other attracts it.”
If your child says… “Heating helps the tiny magnets line up.”
If your child says… “An unmagnetised nail has no magnetised regions.”
Compare the tempting wrong rule with the right idea using a worked visual example before or after practice.
For each idea: show it, ask before you tell, then say one line. (8 hands-on steps with photos and worked examples).
3 · Check understandingQuestions grouped by concept, including 1 with diagrams, each with a clear explanation.
