Light-Dependent Resistor - GCSE Physics Definition

A Light-Dependent Resistor (LDR) is a component used in electronic circuits that changes its resistance based on the amount of light it is exposed to. In the context of GCSE Physics, it's important to understand that an LDR has a high resistance in the dark, which decreases as the light intensity increases, allowing more current to pass through. This property makes LDRs useful in applications such as automatic lighting systems, where they can help detect light levels and trigger a response, for example, switching on a streetlamp at dusk.