Equilibrium in a Single Plane Model MT 120

Sci-tech Equilibrium in a Single Plane Model MT 120, demonstrates the principle of “freeing”, which refers to establishing static equilibrium. The experiment uses a model of a ladder with a sliding clamp weight.


  • Equilibrium conditions and support reactions of a leaning ladder

Item Description

The principle of “freeing” in engineering mechanics allows forces and moments acting on a body to be made visible. In this process, a body or a system such as a bar are virtually removed from the environment. All forces acting on the body or on the system are replaced by standardized symbols.

This results in a simplified model of the body or system, which clearly demonstrates the relationships between forces and moments.


The top support is designed as a movable support and the bottom one as a fixed support. The real effective support forces can be fully compensated by applying cable forces in the x and y directions.

The ladder is in a state of equilibrium without changing the angular position and without the need for structural support. The ladder is “free”. For students, the result is a convincing example for the principle of “freeing” in statics.

The parts of the experiment are clearly laid out and securely housed in a storage system.

Technical Specifications


  1. Development of the static principle of “freeing”
  2. Full compensation of the support forces by cable forces
  3. Sliding clamp weight
  4. Determine the position of the clamp weight via built-in rule with millimetre scale
  5. 2 supports (1x fixed support, 1x movable support)
  6. 3 guide pulleys
  7. Storage system for parts

Technical Specifications:


  • length: 650mm
  • weight: 2N
  • built-in rule, graduation: 1mm

Clamp weight: 20N