| English | Nuclear energy |
|---|---|
| Bahasa Melayu | Tenaga nuklear |
| 中文 | 核能 |
Definition
The energy released from changes in the nucleus of an atom, such as fission or fusion, described by E = mc².
In exam terms
Nuclear energy is the energy released from changes in the nucleus of an atom, such as fission or fusion. It comes from the conversion of a mass defect into energy, described by E = mc², where E is energy in joules (J), m is the mass converted in kilograms (kg) and c is the speed of light, 3.0 × 10⁸ m s⁻¹.
Because c² is very large, even a tiny mass produces an enormous energy. A correct exam line: E = mc² = (2.0 × 10⁻³ kg)(3.0 × 10⁸ m s⁻¹)² = 1.8 × 10¹⁴ J. Nuclear power stations use fission to generate this energy.
Do not confuse it with…
Do not confuse nuclear energy with chemical energy. Nuclear energy comes from changes inside the nucleus and involves a measurable loss of mass; chemical energy comes from the rearrangement of electrons in bonds and involves no measurable mass change.
Nuclear reactions release millions of times more energy per kilogram than chemical reactions.
In Paper 2 this is asked as state what nuclear energy is, or calculate the energy released using E = mc². In a calculation, always convert mass to kilograms and keep c² as (3.0 × 10⁸)² before multiplying, and write the final unit as J.
Source: DSKP KSSM Physics Form 4 and 5 (Versi English) (Bahagian Pembangunan Kurikulum (BPK), KPM)