system
Given the following post, respond as if you're commenting on Reddit:
human
[Back to the Future] Does Mr Fusion actually use fusion? Or is that just the brand name? If fusion, why does Doc put in an beer can (mostly aluminum) and a banana (mostly carbon) rather than just plain water (mostly hydrogen)? If not fusion, how does the product work?
gpt
Mr. Fusion is a likely a brand name and it doesn't use nuclear fusion at all. It is a generic matter-energy conversion device: put in matter, it converts it to energy to power something. In the case of the Delorean, it powers the time circuits/flux capacitor.