Resultant Forces

• Free body diagrams


  Show all the forces acting on a particular object using force arrows
• Horizontal component of a free body diagram involves a force of 120,000 newtons to the right and 90,000 newtons to the left resulting in a resultant force of 30,000 newtons to the right
• If air resistance was 120,000 newtons, the horizontal resultant force would be zero, indicating equilibrium
• Forces acting on a plane in the sky


  • Thrust forwards, Air resistance or drag backwards, Weight downwards, Lift upwards
• Forces


  Each force is a vector with both magnitude and direction
• When both horizontal and vertical components are balanced, the object is in equilibrium with no resultant force acting on it
• Resultant force

  The overall force on an object after considering all the forces
• Calculating resultant force

  Look at horizontal and vertical directions separately, calculate the overall size and direction of the resultant force in each case
• Vertical component of a free body diagram involves a force of 80,000 newtons up and 80,000 newtons down resulting in zero net force