Looks at the series of interconnected clockwork cogs. When you turn the first clockwork cog's handle, which direction will the indicated clockwork cog turn? These physics puzzle cards start out very simple but become ever more complex. Watch out for disconnected cogs, which would result in certain cogs not turning at all.To use Boom Cards, you must be connected to the Internet. Boom Cards play on modern browsers (Chrome, Safari, Firefox, and Edge). Apps are available for Android, iPads, iPhone