Wire framework consisting of a rectangle and triangle

Wire Framework Consisting of a Rectangle and Triangle

Introduction to Wire Frameworks

  • In Further Mechanics, a wire framework is a structure composed of thin, uniform wires arranged to form a shape.
  • These frameworks have negligible thickness and can be treated as line segments.
  • This section will look at a simple wire framework composed of a rectangular and triangular segment.

Wire Frameworks - Finding the Centre of Mass

  • The centre of mass of a wire framework is found by breaking it down into its simpler components - in this case, a rectangle and a triangle.
  • With these individual components, we find their individual centres of mass and their individual moments about a common axis.
  • This is essentially treating each segment of the wire framework as its own separate system, and then combining these at the end.

Centre of Mass in a Rectangle

  • For a rectangle, the centre of mass is simply at the geometric centre - where the diagonals intersect.
  • The distance to the chosen axis is the perpendicular distance from the centre of mass to the line of the axis.

Centre of Mass in a Triangle

  • For a triangle, the centre of mass is located where all the medians intersect, also known as the centroid.
  • The distance to the chosen axis is the perpendicular distance from the centroid to the line of the axis.

Combining the Centres of Mass

  • The moment of each shape about the chosen axis is found by multiplying its mass by its distance from the axis.
  • Add up all the moments to give the total moment and add up all the masses to give the total mass.
  • Finally, divde the total moment by the total mass. The resulting value gives the position of the centre of mass of the entire wire framework.

Practical Application

  • Understanding the centre of mass of a wire framework is useful in various fields, such as physics, engineering, and product design, where creating balanced, stable structures is imperative for successful outcomes.