CHAPTER 4

4.1 (a) Define magnetic field

4.1 (b) Identify magnetic field sources

41 (c) Sketch magnetic field lines for bar magnet, current carrying conductor and Earth's magnetic field

4.2 (a) Sketch resultant magnetic field diagram at a point (limited to two current carrying straight wires and 2D)

4.2 (b) Determine direction of vector B by using right hand rule

4.2 (c) Determine the magnitude of magnetic field by using:

i. B = µ₀I/2πr for a long straight wire

ii. B = µ₀I/2r at the centre of circular coil

iii. B = µ₀nI at the centre of solenoid

iv. B = 1/2µ₀nI at the end of the solenoid

4.3 (a) Explain and use magnetic force, F = qv x B

4.3 (b) Determine the direction of force

4.3 (c) Describe circular motion of a charge in a uniform magnetic field

4.3 (d) Use relationship F_B = F_C

4.4 (a) Explain and use magnetic force, F = IL x B

4.4 (b) Determine direction of forces

4.5 (a) Explain magnetic force per unit length of two parallel current-carrying conductors

4.5 (b) Derived and use magnetic force per unit length, F/l = µ₀ I₁ I₂ /2πd

4.6 (a) Use torque, τ = NIA x B where N = number of turns

4.6 (b) Explain briefly the working principles of a moving coil galvanometer

4.7 (a) Explain the motion of a moving charged particle in magnetic field and electric field for v, B and E are perpendicular to each other

4.7 (b) Use velocity, v = E/B in a velocity selector (eg: Bainbridge mass spectrometer)