Contact and Non-Contact forces

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

  Contact forces and non-contact forces
• How can we describe a force?

  A force is a push or pull that acts on an object due to its interaction with another object
• In what unit do we measure force?

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

  5 newtons
• Why are forces classified as vector quantities?


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

  Contact forces require physical touching, while non-contact forces do not
• Give an example of a contact force.

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

  A contact force
• What is tension in terms of forces?

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

  The reaction force
• How does the normal contact force work with a rock on a table?

  The table exerts an equal and opposite force upwards to support the rock's weight
• What are the three types of non-contact forces mentioned?

  Gravitational force, magnetic force, and electrostatic force
• What is gravitational force?

  A force of attraction between any two objects that have mass
• How do magnetic forces behave?

  They can be attractive or repulsive depending on the poles of the magnets
• What are electrostatic forces?

  Forces between charged objects that can be attractive or repulsive
• How does the strength of non-contact forces change with distance?

  The strength of the force decreases as the objects get further apart
• What are the characteristics of contact forces?

  • Require physical touching between objects
  • Examples include friction, air resistance, tension, and normal contact force
• What are the characteristics of non-contact forces?

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