How does changing the battery voltage affect the brightness of the light?

Changing the battery voltage affects the brightness of a light by altering the amount of electrical current flowing through the circuit. Higher voltage increases the current, which typically results in a brighter light, while lower voltage decreases the current, leading to reduced brightness. However, this relationship can vary depending on the specific characteristics of the light bulb or LED. It's important to ensure that the voltage remains within the safe operating range for the light source to avoid damage.