Forces

• What is a Vector?

  A quantity that has both magnitude and direction.
• What is a scalar?


  A quantity that has just magnitude.
• Describe Electrostatic Force.

  Non - contact

  • The charges cause a force of attraction
• Describe Gravitational Attraction.

  Non - contact

  • The mass creates a force of attraction.
• Describe Normal contact.

  Contact

  • Felt in opposite direction to contact
  • Normal to planes of contact
• Describe Friction

  Contact

  • Surfaces and roughness causes friction when moved in contact
• What is a resultant force?

  A single force representing the sum of all the forces acting on an object.
• What is the formula for work done?


  Work done = force x distance
• Define Elastic Deformation.

  The object returns to its original shape when the load is removed

  • Elastic Band
• Define Plastic Deformation.

  The object does not return to its original shape when load has been removed.

  • A spring is pulled too far
• What is the equation for Hooke's Law?

  $F =$$kx$
• What is the equation for momentum?

  $p =$$mv$
• Describe Newton's First law.

  If a resultant object acts on an object it will accelerate

  • Velocity will change
  • Velocity will change and either speed or direction will change