A student uses a permanent magnet to lift some unmagnetised nails. Some of the nails are made of iron and some are made of steel. Fig. 7.1 shows the magnet lifting the nails. The student leaves the nails attached to the magnet for several hours, then removes the magnet. State a difference between a magnetic property of the iron nails and of the steel nails.

Physics

IGCSE&ALevel

CAIE

Exam No：0625_s23_qp_32 Year：2023 Question No：7(a)(ii)

Answer:

steel nails retain magnetism \(\mathrm{OR}\) are magnetic

4.1.1 Describe the forces between magnets, and between magnets and magnetic materials

4.1.10 Describe methods of demagnetisation, to include hammering, heating and use of alternating current (a.c.) in a coil

4.1.2 Give an account of induced magnetism

4.1.3 Distinguish between magnetic and non-magnetic materials

4.1.4 Describe methods of magnetisation, to include stroking with a magnet, use of direct current (d.c.) in a coil and hammering in a magnetic field

4.1.5 Draw the pattern of magnetic field lines around a bar magnet

4.1.6 Describe an experiment to identify the pattern of magnetic field lines, including the direction

4.1.7 Distinguish between the magnetic properties of soft iron and steel

4.1.8 Distinguish between the design and use of permanent magnets and electromagnets

4.1.9 Explain that magnetic forces are due to interactions between magnetic fields