Why Can't You Raise Your Leg Sideways Against a Wall?

[zainriaz]

Homework Statement

stand with one arm and the side of one foot pressed against a wall. can u raise the other leg side ways?if not then why not?

Homework Equations

The Attempt at a Solution

i tried myself but couldnot raise.i m not getting the reason.

 

[Stonebridge]

Look at the condition for forces in equilibrium, particularly the moment of the force caused by the leg that is moved. (Its moment about the point at which your other leg is supporting you.)
Depending on the level you need to answer this, it may be required for you to look at the shift in position of the body's centre of gravity as a result of the leg movement. Then look at the moment of the force through this point about your point of support.