Science Buddies: "Ask an Expert"

Am building a mass driver model very similar to one posted on this site. Wondering if there is any flyback caused by suddenly deactivating the coils, and if so, would there be protection required(diode, etc)? In circuit diagram provided, none seems to be present. I do not know that much about the topic and I may be worrying too much.


Moderator note: Project: https://www.sciencebuddies.org/science- ... ass-driver