Potential Energy

potential energy

Energy stored by an object by virtue of its position. For example, an object raised above the ground acquires potential energy equal to the work done against the force of gravity; the energy is released as kinetic energy when it falls back to the ground. Similarly, a stretched spring has stored potential energy that is released when the spring is returned to its unstretched state. Other forms of potential energy include electrical potential energy, chemical energy, and nuclear energy.

---

potential energy

the energy of a body or system as a result of its position in an electric, magnetic, or gravitational field. It is measured in joules (SI units), electronvolts, ergs, etc.

---

potential energy [pə′ten·chəl ′en·ər·jē]

(mechanics)

The capacity to do work that a body or system has by virtue of its position or configuration.

---

Potential Energy 

the part of the total mechanical energy of a system that depends on the relative positions of the particles making up the system and on the positions of the particles in the external force field, such as a gravitational field. The potential energy of a system in a given position is numerically equal to the work that the forces acting on the system perform when the system is shifted from this position to a position in which the potential energy is arbitrarily assumed to be equal to zero.

It follows from this definition that the concept of potential energy holds only for conservative systems, that is, systems in which the work of the acting forces depends only on the initial and final positions of the system. Thus, for a weight P raised to a height h, the potential energy will be equal to Ph; it will be equal to zero when h equals zero. For a weight attached to a spring, the potential energy will be 0.5cλ², where λ is the elongation or compression of the spring and c is the spring’s stiffness. Again, the energy is zero when λ is zero. For two particles with masses m₁ and m₂, attracted according to the law of universal gravitation, the potential energy is —fm₁m₂/r, where f is the gravitational constant and r is the distance between the particles. In this case, the energy is zero when r = ∞. The potential energy of two point charges e₁ and e₂ is calculated in a similar manner.

S. M. TARG