Resultant forces

• What is a force defined as?

  A push or pull on an object
• Why are forces considered vector quantities?

  They have both magnitude and direction
• If a man pushes a box with 20 Newtons to the right and a friction force of 10 Newtons acts to the left, what is the resultant force?


  10 Newtons to the right
• What is the resultant force?

  A single force equivalent to all original forces
• How do you calculate the resultant force when two forces act in opposite directions?

  Subtract the smaller force from the larger
• What is the resultant force on the car after calculating the forces?

  1,000 Newtons to the left
• What forces act on the skydiver falling at constant velocity?

  Weight downwards and air resistance upwards
• What is the resultant force when the skydiver is at constant velocity?

  Zero
• What does a Freebody diagram represent?

  Forces acting on an object
• In a Freebody diagram, what does the length of the arrow represent?

  Size of the force
• What does the term altitude refer to in the context of an airplane?

  Height above the ground
• What force acts downwards on the airplane?

  Weight
• What is the force acting in the opposite direction to the weight of the airplane?

  Lift
• What forces must be balanced for the airplane to move at constant velocity?

  Forward and backward forces
• What is the force of air resistance also known as?

  Drag
• What are the steps to draw a Freebody diagram?

  • Represent the object as a point
  • Draw forces as arrows starting at the point
  • Length of arrows shows force size
  • Direction of arrows shows force direction
• What are the key concepts related to resultant forces?

  • Resultant force is a single equivalent force
  • Calculated by subtracting smaller forces from larger
  • Forces can be balanced or unbalanced
  • Freebody diagrams help visualize forces