Past exam of the mathematics course of the University of Cambridge 2023 ii Paper 1 37A c Solution Created 2026-09-24 Updated 2026-09-25
The four-velocity and particle energy areWith the conventions for the given metric, . The temporal component of the covariant Lorentz force is thereforeSince , cancellation of gives the relativistic electromagnetic work-energy theoremThe absence of reflects that magnetic force is perpendicular to the velocity and does no work.