Creating Light!

Below I will detail the creation of my first independent project in Engineering: a flashlight/lantern! The challenge was to create a lantern/flashlight out of three given parts (a 9 volt battery, 3.2 volt LED light, and a resistor) and however many found materials we wanted. The goals of the project were broken down into three categories: functionality, aesthetics, and creative use of materials. In designing my flashlight/lantern, I tried to mix creativity with cuteness, with power.

Designing: 

Here is a sketch of my flashlight/lantern, and a diagram of my circuit:

Calculating: 

Before I set up my circuit, I had to choose the right resistor. To do so I used Ohm's law, V=IR (V for voltage, I for current, and R for resistance). Here are my calculations:

9v battery - 3.2v LED = 5.8v

5.8v = (20mA)(R)

R = 5.8v/20mA

R = 0.29 kΩ

R = 290 Ω

The closest resistor I could find to 290 Ω was 265 Ω, so that is what I used!

Building:

First, I assembled my circuit and made sure the LED lit up. Then, I made the switch and double-checked to make sure the circuit was still working. Below is a picture of the circuit with the switch.

At this point I realized that it would be helpful to have a removable base, because the battery could then be changed when need be.  Below is a picture of the assembled circuit inside the water bottle. 

After this, the decorating process began! I cut holes in the plastic at the base and added ribbon so that the base could be removable. I added colorful card-stock-type paper to the outside of the bottle to cover the messy tape within. I added tinfoil around the head of the bottle to reflect the light from the LED and make it brighter. I then added an obvious tab with an "F" on it to the switch so that it is clear how to use it and to whom it belongs. Below is a picture of the finished product!

As one last touch, I decided to utilize the bottle cap that was left over. I covered the cap in pink tissue paper and fastened it with a rubber band. If the light is used as a lantern, this cap can rest over the LED and create pink light. See below!

 

Reflecting:

In the end, I think I could use this lantern/flashlight in a variety of ways in my room: from ambient lighting to light for reading. If I were to use more LEDs, I might be able to use this as a flashlight outside. 

Although intimidated at first by this project, I ended up really loving the process of creating this useful tool. I learned a lot about circuits, and feel I will retain all of this because I now have the knowledge in my hands. 

I have already gotten commissions from friends who want there own, so maybe I'll make some more of these cuties!