Energy is conserved in all scenarios, even when a force does not do work on an object. When pushing a stationary object, energy is primarily converted to heat due to muscle inefficiency, as the body expends energy to tighten muscle fibers instead of moving the object. In the case of static friction, energy does not dissipate as heat; rather, it remains stored, unlike sliding friction, which does convert energy to heat. Magnetic forces also illustrate this principle, as they do no work on particles due to their perpendicular nature to velocity, conserving the particle's energy. Ultimately, the discussion emphasizes that while energy is conserved, the form it takes can vary depending on the circumstances.