D.3.3—Crossed electric and magnetic fields Topic Practice
D.3.3—Crossed electric and magnetic fields Topic Practice
Practise balancing electric and magnetic forces in crossed fields to find undeflected motion, field strength and the path of new particles.
How this is tested
- set qE = qvB with E = V/d to calculate B from plate p.d., separation and particle speed
- use the field directions and particle charge to sketch whether the new path bends up or down
- choose the magnetic field direction from the page diagram so electric and magnetic forces cancel