For the Science assignment, we did an experiment about the battery life on computer. We have spread into group of four people. My group mate have: Opened around 50 tabs, playing games, listening to music on YouTube, listening to music on iTunes and increasing brightness of computer screen.
As a result, around 50 tabs open+playing games were the most great change of battery decreasing. I think this is because, like as other students might say, opening lots of tabs could be using lots of batteries, and in addition games or something to do with online could consume batteries.
Here is the chart for the experiment:

