Navigation Links
Jump rope aerodynamics
Date:11/21/2010

WASHINGTON, D.C., November 21, 2010 -- Jump ropes are used by kids for fun and by athletes for training. But what about the underlying physics? How do jump ropes work? Can important engineering principles be studied?

Jeff Aristoff and Howard Stone of Princeton University have built themselves a robotic jump rope device that controls all the rope parameters -- rope rotation rate, rope density, diameter, length, and the distance between "hands." They capture the motion of the ropes by high-speed cameras, one to the side and one at the end. Then they compare the observed behavior with predictions made by their equations -- work they are presenting today at the American Physical Society Division of Fluid Dynamics (DFD) meeting in Long Beach, CA.

"Our main discovery is how the air-induced drag affects the shape of the rope and the work necessary to rotate it," says Princeton researcher Jeff Aristoff. "Aerodynamic forces cause the rope to bend in such a way that the total drag is reduced." (Leaves do this too when they bend out of the wind.) This deflection or twisting is most important in the middle of the rope and the least at the ends. If the rope is too light it might not clear the body of the jumper.

"Implications for successful skipping will be discussed, and a demonstration is possible," said Aristoff about his presentation at the meeting. "Fluid dynamic effects on long flexible filaments occur in both engineered structures and many natural systems, so insights from the jump rope will hopefully inform other common situations," he added.


'/>"/>

Contact: Jason Socrates Bardi
jbardi@aip.org
301-209-3091
American Institute of Physics
Source:Eurekalert

Page: 1

Post Your Comments:
*Name:
*Comment:
*Email:
(Date:5/16/2017)...   Bridge Patient Portal , an enterprise ... EMR Systems , an electronic medical record solutions ... established a partnership to build an interface between ... Centricity™ products, including Centricity Practice Solution (CPS), Centricity ... new integrations will allow healthcare delivery networks using ...
(Date:4/17/2017)... 17, 2017 NXT-ID, Inc. (NASDAQ: NXTD ... filing of its 2016 Annual Report on Form 10-K on Thursday ... ... available in the Investor Relations section of the Company,s website at ... website at http://www.sec.gov . 2016 Year Highlights: ...
(Date:4/11/2017)... 11, 2017 No two people are ... the New York University Tandon School of Engineering ... found that partial similarities between prints are common ... mobile phones and other electronic devices can be ... vulnerability lies in the fact that fingerprint-based authentication ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... ComplianceOnline’s Medical Device Summit is back for ... June 2018 in San Francisco, CA. The Summit brings together current and former FDA ... board directors and government officials from around the world to address key issues in ...
(Date:10/11/2017)... HILLS, Calif. , Oct. 11, 2017  SkylineDx today ... (ICR) and University of Leeds ... risk-stratify patients with multiple myeloma (MM), in a multi-centric Phase ... University of Leeds is the sponsor ... and ICR will perform the testing services to include high-risk ...
(Date:10/11/2017)... Bay, Florida (PRWEB) , ... October 11, 2017 ... ... and Drug Administration (FDA) has granted orphan drug designation to SBT-100, its novel ... (sdAb) for the treatment of osteosarcoma. SBT-100 is able to cross the cell ...
(Date:10/10/2017)... ... October 10, 2017 , ... For the ... won a US2020 STEM Mentoring Award. Representatives of the FirstHand program travelled to ... Experience from US2020. , US2020’s mission is to change the trajectory of STEM ...
Breaking Biology Technology: