Final answer:
A photoresistor's resistance decreases when exposed to light, which is the opposite behavior of a traditional resistor where the energy is converted into heat, affecting light emission and circuit current.
Step-by-step explanation:
A photoresistor is an electronic component whose electrical resistance decreases when it is exposed to light. This behavior is due to the nature of photoresistors where the increase in light intensity reduces the resistance by causing more charge carriers to be available, thus allowing more current to flow through.
In a traditional resistor, electrical energy is converted into heat energy, and this can be observed in incandescent light bulbs, where the resistor (filament) gets so hot that it emits light.
The color of the light emitted by an incandescent bulb can change with resistance; if the resistance is increased, the filament does not get as hot, and thus, it will emit a redder light, indicative of a lower temperature. In circuits, adding more resistors in series increases the overall resistance, which according to Ohm's law, reduces the current in the circuit as the voltage remains constant.