vector diagrams

• When several forces act on an object, they can be replaced by a single force which has the same effect, called the resultant force
• Vector diagram


  A scale drawing showing the forces involved
• Steps to calculate resultant force using vector diagram

  1. Draw 10 cm arrow to represent 10 N force

  2. Use protractor to measure 30 degree angle

  3. Draw 8 cm arrow to represent 8 N force

  4. Create parallelogram

  5. Measure length of resultant vector

  6. Calculate resultant force
• Scale


  Relationship between diagram measurements and actual force magnitudes
• Steps to calculate resultant force for 280 N and 320 N forces at 20 degrees

  1. Decide on scale (e.g. 1 cm = 40 N)

  2. Draw vector diagram to scale

  3. Complete parallelogram

  4. Measure resultant vector length

  5. Calculate resultant force