Gravity Light

In this assignment, we were asked to estimate the weight that is required to power the GravityLight.

Previous knowledge:
The LED lights that we used in class were 3.2v 20mA
Gravity= 9.8 m/s2

Because it was mentioned in the article that the bag used to weigh the light down is typically filled with rocks and sand, I used my previous knowledge of how heavy those would be. I then looked at the bag as depicted in the pictures on the article and assessed that it was about 10x5x4 in3. I then assumed that in that bag one could fit approximately 15 to 20 rocks. Assuming that each rock weighs .25 lbs, the bag would come out to weigh approximately 5 lbs.

This product absolutely seems viable. It is low risk because it does not cause many safety hazards and it is cheap and sustainable. Most importantly, it works. I can see this product being used in years to come although a good improvement would be to make the LED last longer.