A technician wants to build the strongest possible solenoid for use in a medical imaging device. Describe five factors the technician could change to increase the strength of the magnetic field produced by the solenoid.

OCR A-Level Physics A (H556) — 4.4 Waves · Describe · 5 marks · View as Markdown

Written & reviewed by James Millett — Biology (Imperial College London), PGCE Science (University of Cambridge).

A solenoid is a wire wrapped into the shape of a coil. The strength of its magnetic field can be altered by changing several physical properties of the solenoid.

Model answer (5 marks)

1. Increase the electric current flowing through the coil.
2. Increase the number of turns of wire in the coil.
3. Insert an iron core into the centre of the solenoid.
4. Increase the length of the coil.
5. Increase the cross‑sectional area of the solenoid.

Examiner tips

  • Use the exact wording from the mark scheme – e.g. "increase the current", "increase the number of turns", etc.
  • Show the points in a clear, numbered list so each criterion is obvious.
  • Remember the question asks for five factors – no more, no less.
  • Use UK spelling (e.g. "colour", "organisation").

Common mistakes

  • Writing the factors in a paragraph instead of a numbered list, making it hard to see all five. Using vague terms such as "make it bigger" instead of the specific factors. Omitting the iron core or the cross‑sectional area, which are both required by the mark scheme.

Mark scheme (5 marks)

  1. Increase the size of the current flowing through the solenoid
  2. Increase the number of turns (coils) of wire
  3. Insert an iron core into the centre of the solenoid
  4. Increase the length of the coil
  5. Increase the cross-sectional area of the solenoid

Key terms in this question

solenoid · magnetic field

Related

More Waves questions

▶ Try answering this question with AI marking (free) →