Resolving forces

• Vector diagram

  Used to resolve a single force into two forces
• Resolving a single force into two components

  1. Draw faint lines for horizontal and vertical axes

  2. Use protractor to measure angle from horizontal

  3. Draw vector to scale representing the force

  4. Draw dotted lines from head of vector to horizontal and vertical axes

  5. Draw horizontal and vertical components
• Resolving a force

  • 100 Newton force acting at 35 degrees with horizontal
  • 75 Newton force acting at 20 degrees with horizontal
• Horizontal component

  • Magnitude determined by measuring length of horizontal component on vector diagram
• Vertical component

  • Magnitude determined by measuring length of vertical component on vector diagram
• The horizontal and vertical components must be at right angles to each other
• In the exam, it's a good idea to blob out any faint lines used to construct the vector diagram, only showing the final vectors
• For the 75 Newton force at 20 degrees, the horizontal component is 70 Newtons and the vertical component is 25 Newtons