What occurrence is characterized by high resistance and increased heating at the contact points?

Loose connections occur when electrical connections are not secure, leading to high resistance at the contact points. This resistance generates heat as electrical current passes through, which can lead to various potential hazards, including arcing and equipment failure.

The increased resistance at these connections means that more energy is lost as heat instead of being used effectively for the intended electrical purpose. If the heat generated is not dissipated properly, it can result in insulation damage, ignition of surrounding materials, or even a fire.

Understanding the specific nature of loose connections is crucial for fire investigators, as they can be a significant contributor to electrical fires. In contrast, circuit overloads occur when too much current flows through a circuit, ground faults involve unintended paths for current to flow, and short circuits happen when electricity takes an unintended path with low resistance, which causes large amounts of current to flow. Each of these scenarios presents different risks and behaviors in electrical systems, but the defining feature of loose connections is the high resistance and subsequent heating at the contact points.