ConceptConceptDocsDocuments

CAIE A-Level Physics 20.5.2 Using Φ = BA

Practise calculating magnetic flux with Phi = BA, rearranging for field strength or area, and checking perpendicular geometry and units.

Syllabus
2028–2030
Course
Physics 9702
Level
A2

Exam points

  • calculate magnetic flux using Phi = BA
  • rearrange the relationship to determine B or A and use consistent units

20.5.2—Φ = BA question 1

[Maximum number: 1]

A small solenoid of area of cross section 1.6×10−3 m21.6 \times 10^{-3} \mathrm{~m}^{2} is placed inside a larger solenoid of area of cross-section 6.4×10−3 m26.4 \times 10^{-3} \mathrm{~m}^{2}, as shown in Fig. 6.1.

Fig. 6.1 (not to scale)

Fig. 6.1 (not to scale)

The larger solenoid has 600 turns and is attached to a d.c. power supply to create a magnetic field.

The smaller solenoid has 3000 turns.

Compare the magnetic flux in the two solenoids.

All question bank results loaded