Edexcel A-Level Physics Atomic Mass Unit

Practise Edexcel A-Level Physics atomic mass unit conversions by linking tiny nuclear masses to SI units, joules and MeV energy values.

Exam points

convert masses in atomic mass units to kilograms before applying E = mc²
show that a 1 u mass decrease corresponds to about 930 MeV of released energy

[Maximum number: 4]

Actinium-225 is a radioactive isotope. It decays to francium by emitting alpha particles. Actinium-225 has a short half-life, which makes it suitable for medical applications.

In a radioactive decay, energy is released and the total mass decreases.

Show that the energy released if the mass decreases by 1 u is about 930 MeV .

All question bank results loaded

5.4.134 - Atomic mass unit question 1