Forces

• What is a scalar quantity?

  Magnitude only
• What is a vector quantity?

  Magnitude and associated direction
• What is a force?

  a push or pull that acts on an object due to the interaction with another object
• What is a contact force?

  when the objects are physically touching
• What is a non-contact force?

  When the objects are physically separated
• What are some examples of contact forces?

  • friction
  • air resistance
  • tension
  • normal contact force
• What are some examples of non-contact force?

  • Gravity
  • Magnetic
  • Electrostatic
• What quantity is Force?

  Vector
• What is Weight?

  The force acting on an object due to gravity. The weight depends on the gravitational field strength of the area
• What is gravity on earth?

  9.8 N/kg
• What is the equation linking weight, mass and gravity?

  $weight\ =$$\ mass\ \times gravitational\ field\ strength\$
• What is the relationship between mass and weight?

  Weight is directly proportional to the mass ($W\ \infty\ m$)
• How is the weight measured?

  Newtonmeter
• What is the middle point in a vector diagram?

  Centre of mass
• What is the resultant force?

  A single force that has the same effect as all the original forces acting together