When something irritates the nerve endings of your nose you take a deep breath and sneeze at over 160km/h (100mph). Bless you!
For a study published this year, Tang and his colleagues used high-speed cameras to take pictures of pepper-induced sneezes from six volunteers. The team captured each sneeze by positioning the volunteers in front of a concave mirror and then shining an LED beam toward it. The warm air from the sneeze has a different refractive index than the cooler ambient air, so the reflected LED bends differently. The camera records the changes, and scientists can map the sneeze.
The study found that a sneeze’s maximum velocity is nowhere near 100 meters per second but instead reaches a high of 4.5 meters per second, or 10 miles per hour. That’s comparable to the velocity of air expelled by coughing—and a violent cough can push up a larger volume of air, which requires even more force. “The sneeze is really coming from your upper respiratory tract,” Tang explains.
Tang, who did his study in Singapore, acknowledges that his numbers might have come out differently if he’d chosen different subjects. “All my data is from these rather slim Asian students,” he says. “If somebody did this in the North American setting, with the bigger body frames that they have here, they might find higher velocities.”
Credit : Popular Science
Picture Credit : Google
