Contact and Non-contact Forces

• What are the two types of forces discussed in the video?

  Contact forces and non-contact forces
• How is a force defined in the context of this video?

  A push or pull acting on an object
• In what unit do we measure force?

  Newtons
• If a hand pushes a box with a force of five newtons, what is the force exerted?


  Five newtons
• Why are forces classified as vector quantities?

  Because they have both magnitude and direction
• What is the key difference between contact and non-contact forces?

  Contact forces require physical touching
• What is an example of a contact force?

  Friction between a board and sand
• What is air resistance classified as?

  A contact force
• How is tension defined in the context of forces?

  As a pulling force exerted through a rope
• What is the normal contact force also known as?

  The reaction force
• What does the normal contact force do in the example of a rock on a table?

  It exerts an equal and opposite force upwards
• What are the three types of non-contact forces mentioned?

  Gravitational, magnetic, and electrostatic forces
• How do non-contact forces act?

  They can act through empty space
• What is gravitational force?

  A force of attraction between masses
• What happens to the strength of non-contact forces as objects get further apart?

  The strength of the force decreases
• How do magnetic forces behave?

  They can be attractive or repulsive
• What can electrostatic forces be between?

  Charged objects
• What is the relationship between electrostatic forces and distance?

  Strength decreases as distance increases
• What are the characteristics of contact forces?

  • Require physical touching
  • Examples include friction and tension
  • Act directly between objects
• What are the characteristics of non-contact forces?

  • Do not require physical touching
  • Examples include gravitational, magnetic, and electrostatic forces
  • Act through fields of influence