<P> Nuclear potential energy is the potential energy of the particles inside an atomic nucleus . The nuclear particles are bound together by the strong nuclear force . Weak nuclear forces provide the potential energy for certain kinds of radioactive decay, such as beta decay . </P> <P> Nuclear particles like protons and neutrons are not destroyed in fission and fusion processes, but collections of them can have less mass than if they were individually free, in which case this mass difference can be liberated as heat and radiation in nuclear reactions (the heat and radiation have the missing mass, but it often escapes from the system, where it is not measured). The energy from the Sun is an example of this form of energy conversion . In the Sun, the process of hydrogen fusion converts about 4 million tonnes of solar matter per second into electromagnetic energy, which is radiated into space . </P> <P> Potential energy is closely linked with forces . If the work done by a force on a body that moves from A to B does not depend on the path between these points, then the work of this force measured from A assigns a scalar value to every other point in space and defines a scalar potential field . In this case, the force can be defined as the negative of the vector gradient of the potential field . </P> <P> For example, gravity is a conservative force . The associated potential is the gravitational potential, often denoted by φ (\ displaystyle \ phi) or V (\ displaystyle V), corresponding to the energy per unit mass as a function of position . The gravitational potential energy of two particles of mass M and m separated by a distance r is </P>

What is the scientific definition of energy that relate it to work