Why do boomerangs return? How do painkillers know where to go? Are some painkillers faster than others? Why do men have nipples? We take on these questions in this week's show as well as find out why rainbows form arcs, what Menieres disease is, how sea breezes form and why we don't sing with accents. We also investigate the difference between X-rays, MRIs and other medical scans! Like this podcast? Please help us by supporting the Naked Scientists