1K20.35-Angle of Repose


Video: Watch this demo – Wood

Watch this demo – Sandpaper

YouTube video showing angle of repose using sand piles

Description: A demonstration to show the angle of repose: the angle at which gravity overcomes the force of static friction and the block starts to slide.


  • Angle of repose apparatus (see photo)
  • Blocks of various masses and material
  • Wooden block
  • Brick
  • Block with sandpaper
  • Block with leather
  • Plastic block

Setup Procedure:

  1. Gather together all the materials; make sure everything is in working order.

Demonstration Procedure:

  1. Place block at the top of the ramp.
  2. To adjust the angle, loosen the wing nut on the apparatus.
  3. Find the angle of repose.

Concepts: Shows the concept of angle of repose. Can be used to show the approximation that:

Tan(theta) = Mu sub s where, μs is the coefficient of static friction, and θ is the angle of repose.