Convert Electronvolts to Megajoules
Convert Electronvolts (eV) to Megajoules (MJ) instantly and accurately.
Conversion Formula
MJ = eV × 1.602176634e-25
About Electronvolts
An electronvolt (eV) is the kinetic energy gained by one electron accelerated through 1 volt - exactly 1.602176634 × 10⁻¹⁹ J (fixed by the 2019 SI revision). It is the natural energy unit of atomic and particle physics: visible light photons carry 1.7-3.1 eV; hydrogen ionisation requires 13.6 eV; X-ray photons span 100 eV-100 keV; protons at the LHC reach 6.5 TeV. Rest masses use eV/c²: electron 0.511 MeV, proton 938.3 MeV, Higgs boson 125 GeV. Nuclear binding energy peaks at ~8 MeV/nucleon for iron-56. 1 eV = 1.602176634 × 10⁻¹⁹ J.
About Megajoules
A megajoule (MJ) is 10⁶ J - the scale of fuel combustion in vehicles and kinetic energy of road traffic. Energy content: 1 L diesel ~34.9 MJ; 1 L petrol ~32.2 MJ. A 1,500 kg car at 100 km/h has KE = ½ × 1,500 × 27.78² ≈ 0.579 MJ; at 200 km/h it carries 2.31 MJ - explaining crash severity's quadratic speed dependence. A 60 kWh EV battery stores 60 × 3.6 = 216 MJ. Detonation of 1 kg TNT releases 4.184 MJ. Adults at rest metabolise ~6-9 MJ/day. 1 MJ = 10⁶ J = 239.0 kcal = 0.27778 kWh = 947.8 BTU.
Quick Reference Table
| Electronvolts (eV) | Megajoules (MJ) |
|---|---|
| 1 eV | 1.602 × 10-25 MJ |
| 2 eV | 3.204 × 10-25 MJ |
| 5 eV | 8.011 × 10-25 MJ |
| 10 eV | 1.602 × 10-24 MJ |
| 25 eV | 4.005 × 10-24 MJ |
| 50 eV | 8.011 × 10-24 MJ |
| 100 eV | 1.602 × 10-23 MJ |