The pictures demonstrates the internal structures of an LED flashlight and expalin how it funtions.
Overall, the flashlight comprises a bulb, two batteries connected to a metal spring, a switch with metal contacts at each end. The light is turned on or off completing or breaking an electric circuit that allows current to pass through the bulb and emit light.
Inside the flashlight, a bulb is placed on the top, connected to two batteries that are placed on top of one another and serve as the power sources. At the bottom, a metal spring connects to the negative terminal of the lower battert and facilitates guide the current upward through the stack of battery to reach the lightbulb.
To the side of the batteries is a slide switch, which contains one metal contact at each end. In the “off” position, the circuit is broken because the contacts do not touch. When light is needed, the switch is slid downward, and the metal contacts meet and close the circuit. This allows electricity to travel from the batteries to the LED buln at the top, emitting light as intended