• Magnetic Field: Causes charges to move in a circular path.
• Electric Field: Causes charges to move in a parabolic path.
• Combine both fields at right angles for special effects!

💡 Real-world Example: Imagine a racing track (magnetic field) with walls (electric field). Cars (charged particles) would go in circles, but walls can change their path!

• When electric (FE) and magnetic (FB) forces balance, the charge goes straight.
• Formula time! FE = FB => qE = qvB => v = E/B
• Perfect balance at a specific E:B ratio = velocity selector!

💡 Real-world Example: Think of a slide where you need a specific speed to slide straight without being pushed left or right. Too slow? You're pushed one way. Too fast? Pushed the other way!

Electron in crossed electric & magnetic fields

• Magnetic Field = 50mT
• Tasks: a. Find velocity (v) for electric field = 7.5kVm⁻¹ b. Find electric field (E) for v = 2.4 × 10⁴ms–1
• Solutions: a. v = E/B = 7.5 × 10³ / 5.0 × 10^–2 = 1.5 × 10⁵ms^–1. b. E = Bv = 5.0 × 10^–2 × 2.4 × 10⁴ = 1.2 × 10³ Vm^–1.

• Combines electric & magnetic fields for cool purposes.
• Two main parts
  • Velocity selector: Electric & magnetic fields.
  • Deflection chamber: Just magnetic field.
• Different charged ions = different circular paths.

💡 Real-world Example: Think of a funfair ride where cars (ions) with different weights (mass) take different tracks. The place where they stop tells us about their weight!