Jump to content
Sign in to follow this  
  • entries
  • comments
  • views

Physics APC or ATC?

Sign in to follow this  


Recently I went to an indoor climbing facility downtown, called Rock Ventures. I love rock climbing, there's a thrill in all that built up gravitational potential energy. However, it is completely safe thanks to our friend the pulley. There are multiple types of rock climbing, indoor climbing, free climbing, and solo climbing. Solo climbing has no ropes involved whatsoever, just a person on a cliff. Free climbers use ropes, but only to prevent from injury in segments, not to assist in the climb. Indoor or sport climbing is what I was doing, this type involves a pulley system. The interesting part of this system, not really having to do with pulleys, is the ATC that is used when belaying (yes it stands for Air Traffic Controller, you'll soon see why)

The ATC is used by the belayer, a person on the ground spotting the climber, to control their ascent and descent and how much slack is in the rope. The ATC is a device which the rope goes through to be manipulated by the belayer. There is a lead rope and a slack rope, when they are parallel, the rope is free to slide - in this position the belayer can pull excess rope through as the climber ascends, getting rid of slack makes the climb safer in case the climber would fall. When the slack part of the rope is pulled down towards the ground, there is a frictional force between the ATC and the rope, which under even a large amount of tension, would not allow the rope to slide.

The ATC is a very simple, yet genius device that makes it possible to safely climb for fun, and for that, I thank physics


Sign in to follow this  


Recommended Comments

I wish I could climb a rock wall. Sometimes I have rock climbing in gym class but those opportunities are few and far between.

Share this comment

Link to comment

Used to go to Rock Ventures all the time (nearly 20 years ago) -- it's been around for a while now.  Cool stuff -- love all the tensions and physics in the knots!

Share this comment

Link to comment
Add a comment...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Terms of Use

The pages of APlusPhysics.com, Physics in Action podcasts, and other online media at this site are made available as a service to physics students, instructors, and others. Their use is encouraged and is free of charge. Teachers who wish to use materials either in a classroom demonstration format or as part of an interactive activity/lesson are granted permission (and encouraged) to do so. Linking to information on this site is allowed and encouraged, but content from APlusPhysics may not be made available elsewhere on the Internet without the author's written permission.

Copyright Notice

APlusPhysics.com, Silly Beagle Productions and Physics In Action materials are copyright protected and the author restricts their use to online usage through a live internet connection. Any downloading of files to other storage devices (hard drives, web servers, school servers, CDs, etc.) with the exception of Physics In Action podcast episodes is prohibited. The use of images, text and animations in other projects (including non-profit endeavors) is also prohibited. Requests for permission to use such material on other projects may be submitted in writing to info@aplusphysics.com. Licensing of the content of APlusPhysics.com for other uses may be considered in the future.

  • Create New...