I was given a chance to build a flashlight using any tool(s) or technique(s) I would like, and according to Ben’s definition on flashlight, I believe my flashlight does have the features of portable, battery powered, and creates light.
I started with 4 button batteries, and tried to light up a LED by connecting + and ground to the LED. As the LED lighted up, I basically got the logic of making my flashlight.
After that I made the exterior of the flashlight by drilling a hole (for inserting everything in) and smoothening the surface (for better grip) on a piece of wood. I inserted everything inside and added a switch to the circuit for the purpose of turning on and off the flashlight.
Since 4 nickel batteries might exceeds the voltage that a LED can handle, I added a resistor to the circuit to prevent LED burnt. After everything went into the wooden hold, it turned out to be like this.
Although at this point it is pretty much done, I did not like it since it looks way too sketchy. Therefore, I cleaned it up (hid the wires and added a LED holder on the top of the flashlight) and made it looks better.