How do roller coaster designers go from dream to reality? World-renowned roller coaster designer Alan Schilke tells us how he does it. Also — why do some people feel sick or dizzy after riding them? And how do coasters make you feel like you’re floating? Plus: a tricky mystery sound and a Moment of Um that answers the question, “How do boomerangs come back?” This episode is sponsored by Quip (getquip.com/brainson), Thoughtfully (thoughtfully.com/brains) and Little Passports (LittlePassports.com/brains).