Final answer:
Energy expressed in terms of variables q and c depends on the context and could refer to electric potential energy in a two-charge system or relate to conservation of energy in thermodynamics.
Step-by-step explanation:
To express energy in terms of the variables q (charge) and c (speed of light), we can refer to the equation E = mc², where E represents energy, m represents mass, and c is the speed of light in a vacuum. For a system where mass and energy are conserved, an energy change ΔE can be associated with a mass change Δm, with ΔE = Δmc². However, if we are dealing with electric potential energy in a two-charge system, we might be looking at an equation like U = kq1q2/r, where k is Coulomb's constant, q1 and q2 are the charges, and r is the separation distance. In another context, if we're discussing thermodynamics and referring to heat (Q), the energy W of a system can be expressed using the conservation of energy as W = Qh - Qc, where Qh is the heat absorbed and Qc is the heat released. The specific expression will depend on the context of the system being analyzed.