OCT 01, 2019 6:30 AM PDT

What do a Wing Nut and a Tennis Racket Have in Common?

WRITTEN BY: Daniel Duan

In 1985 during a mission to rescue the space station Salyut-7, Soviet astronaut Vladimir Dzhanibekov observed something rather strange: a free-flowing wingnut spun around its central axis for a few seconds, and without any force applied, it suddenly flipped 180 degrees to the opposite direction and continued spinning. 

He thought of it as a fresh discovery, but little did he know mechanisms of this mysterious movement have been described in classical mechanics for over a century. He was not alone, however. In 1991, a team of U.S. and Netherland researchers also reported what they believed was the first-of-its-kind discovery, about a weird behavior about a twisting tennis racket.

For example, when twisted by its handle or tossed with the net facing sideways, the racket maintains its rotational position until it hits the ground; but when you throw the racket with its net facing up/down, along its intermediate axis, a bizarre thing happens: it turns 180-degree mid-air. 

Both phenomena can be explained with the intermediate axis theorem. A solid, symmetrical object such as a tennis racket have three rotational axes — the ones with the maximum or minimum moment of inertia, and the one with intermediate moment of inertia. The theorem suggest that when an object spins exactly around its intermediate axis, the centrifugal force slowly accumulates and destabilizes its position, eventually leading to the object flipping to a position at the opposite direction.

Back to Dzhanibekov's moment of discovery, the Soviet astronaut did not take what he saw as a stroke of serendipity. Because he realized that a potentially apocalyptic consequence might be associated to this phenomenon, therefore keeping it as a secret. Want to find out what triggered Dzhanibekov's fear? Watch the video from Veritasium in full to find out yourself (spoiler alert: it is a-okay after all) 

Source: Veritasium via Youtube

About the Author
  • Graduated with a bachelor degree in Pharmaceutical Science and a master degree in neuropharmacology, Daniel is a radiopharmaceutical and radiobiology expert based in Ottawa, Canada. With years of experience in biomedical R&D, Daniel is very into writing. He is constantly fascinated by what's happening in the world of science. He hopes to capture the public's interest and promote scientific literacy with his trending news articles. The recurring topics in his Chemistry & Physics trending news section include alternative energy, material science, theoretical physics, medical imaging, and green chemistry.
You May Also Like
SEP 04, 2020
Microbiology
Researchers Discover a Way to Use Microbes to Help Make Plastic
SEP 04, 2020
Researchers Discover a Way to Use Microbes to Help Make Plastic
Researchers have discovered that some bacteria can make ethylene in a way we never knew about; microbes that metabolize ...
SEP 22, 2020
Chemistry & Physics
New photodectector can see the full light spectrum
SEP 22, 2020
New photodectector can see the full light spectrum
New research from a team at RMIT University highlights the development of a hyper-efficient broadband photodetector that ...
OCT 10, 2020
Chemistry & Physics
Imagining the sunspots of other solar systems
OCT 10, 2020
Imagining the sunspots of other solar systems
A recent study published in the Astrophysical Journal takes a new look at sunspots in order to understand stellar activi ...
OCT 20, 2020
Chemistry & Physics
How to generate visible laser light on microchips
OCT 20, 2020
How to generate visible laser light on microchips
A new study reported in the journal Optica highlights the development of a microchip technology that can convert invisib ...
OCT 29, 2020
Chemistry & Physics
Einstein: Gravity? What Gravity?
OCT 29, 2020
Einstein: Gravity? What Gravity?
Try imagining a fictional conversation between Issac Newton and Albert Einstein: "The apple falls toward the ground ...
NOV 15, 2020
Chemistry & Physics
Chemical reactivity flowcharts assist chemists in interpreting reaction outcomes
NOV 15, 2020
Chemical reactivity flowcharts assist chemists in interpreting reaction outcomes
New research published in Organic Letters from Purdue University scientists presents the design and development of ...
Loading Comments...