There are optical illusions and audio illusions. Is there such a thing as an olfactory illusion?
Justin Baker
Melbourne, Australia
What forces are acting on a particle of fluid that makes it start spiralling or moving helically down a pipe instead of flowing smoothly?
Phil Morey
via email
Last Word is New Scientist鈥檚 long-running series in which readers give scientific answers to each other鈥檚 questions, ranging from the minutiae of everyday life to absurd astronomical hypotheticals. To answer a question or ask a new one, email lastword@newscientist.comTo answer this question 鈥� or ask a new one 鈥� email lastword@newscientist.com.
Advertisement
Questions should be scientific enquiries about everyday phenomena, and both questions and answers should be concise. We reserve the right to edit items for clarity and style. Please include a postal address, daytime telephone number and email address.
The use of AI tools (e.g. ChatGPT, Claude) to write either questions or answers is forbidden, and any submissions found to have been written using AI tools will be withdrawn.
