Readers ask about buoyancy, Stonehenge sounds and more

cover of the September 26, 2020 issue

Rock the boat Scientists made a toy boat float upside down on the bottom of a layer of levitating liquid, Maria Temming reported in “Toy boats defy gravity by floating upside down” (SN: 9/26/20, p. 32). “I was quite intrigued by the upside-down boat. The explanation of buoyancy versus gravity does suggest an equilibrium for […]