You are Here: Home >< Physics

# Need help with stable equilibrium concept watch

1. So the standard explanation of stable equilibrium is "when the centre of mass of a body is directly below the point of suspension or support...when a body of such orientation is displaced it will return to its original position (due to resultant torque produced)". But in the instance that such a body is displaced at such an angle that the line of action of its weight is outside its base, the body in "stable equilibrium" will have changed position, right? So how can the body be in stable equilibrium? Or is this explanation only appropriate with the provision that the displacement isn't beyond the tilting point?

P.S. consider a book that is originally flat on a table which is displaced/tilted beyond the standing position (if you're not understanding my point). THANKS!
2. Sorry you've not had any responses about this. Are you sure you’ve posted in the right place? Posting in the specific Study Help forum should help get responses.

I'm going to quote in Tank Girl now so she can move your thread to the right place if it's needed.

Spoiler:
Show
(Original post by Tank Girl)
x
3. You're quoting a definition where the centre of mass is lower than the point of support and providing a counterexample (book standing on a table) where the centre of mass is higher than the point of support.

I think your book on a table is an example of a metastable system - one with several stable positions you can push it between.

### Related university courses

TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Updated: November 2, 2015
Today on TSR

### Exam Jam 2018

Join thousands of students this half term

### Solo - A Star Wars Story

Poll

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE