A student makes a solenoid by winding insulated wire into a coil.
Which change makes the magnetic field of the solenoid stronger?
Placing an iron core inside the coil
Using fewer turns of wire on the coil
Decreasing the current in the coil
Placing a copper core inside the coil
44 exam-style questions on OCR GCSE Physics 4.1 Magnets and magnetic fields, covering 4.1.1 Magnetic poles, attraction and repulsion, 4.1.2 Permanent and induced magnets, 4.1.3 The magnetic field of a magnet, 4.1.4 Compasses and the Earth's magnetic field, 4.1.5 The magnetic field around a current-carrying wire, 4.1.6 Field strength, current and distance, and 4.1.7 Solenoids and electromagnets. Each one has a worked solution and a mark scheme showing where the marks go.