hep

Relativistic energy from momentum and rest mass

In special relativity, a particle's total energy E, momentum p, and rest mass m are related by the energy-momentum relation. Working in natural units (c = 1), it simplifies to E^2 = p^2 + m^2.

A particle has rest mass m = 1 GeV and momentum p = 2 GeV. What is its total energy E, in GeV? Give your answer to 2 decimal places.