Measure the speed of a sneeze

The speed of a sneeze is 4.5m / s, not as big as 100m / s as people know before.

In a recent study, Canadian scientists used high-tech camcorders to photograph the process of sneezing created by six volunteers. They gave the volunteers to stand in front of a concave mirror and project a beam of LED light towards it.

The warmer air from sneezing has a different refractive index than the cooler air around it, so the LED light is bent differently. The camera recorded changes and scientists can replicate this process.

Measure the speed of sneezing.(Photo: Psu)

The results show that the maximum velocity of sneezing does not reach 100m / s as previously known but instead is 4.5m / s, which is equivalent to air velocity when people cough."Sneezing comes from our upper respiratory tract , " said Julian Tan from the public health laboratory in Edmonton, Alberta.

He and his colleagues in Singapore acknowledge that this number varies if different subjects are selected."All my data comes from a few students in Asia, if someone in North America participates in the experiment, with a larger body frame they will create higher velocities , " he said.

According to Popsci, for a long time it was thought that the speed of a sneeze was about 100 meters per second, but that seemed an exaggerated number. This number comes from a researcher named William Firth Wells, who analyzed the size of air droplets from an air sneeze to infer its speed.

The 100m / s figure has existed for many years but has never been tested directly in the laboratory."I think people are waiting for someone to expose this issue," Julian Tan said.