Resumen de The ladder against the wall revisited

Iain Maclnnes, John Huxtable

• When placing a ladder against a wall, what is the maximum angle from the wall to ensure the ladder won't slip? A simple experiment to determine the relationship between the angle and the coefficient of friction (µ) is described. Leading on from this, some thought is given to the implications of a negative value for the coefficient of friction, which the mathematical analysis suggests should be possible.