What are Forces?

KEY IDEAS

  • All forces are pushes or pulls, or a combination of them (bends and twists)
  • Forces are responsible for changes in motion
  • Forces are invisible

EXAMPLE QUESTIONS

  • What do you think forces are?
  • Can you see a force?
  • What do forces do?

FORCES ARE PUSHES, PULLS, OR COMBINATIONS OF PUSHES AND PULLS

  • All forces are pushes or pulls.
  • Twists and bends are combinations of pushes and pulls.

FORCES ARE INVISIBLE

  • There are many types of forces (electrical, magnetic or gravitational, for example).
  • We cannot actually see a force; we can see only the effects or results of a force.

UNBALANCED FORCES CAUSE CHANGES IN MOTION

  • Pushes and pulls cause things to start moving, speed up, slow down, change direction or stop moving.
  • All changes in motion happen because of unbalanced forces.
  • Motion increases when a force is being exerted.
  • Motion stops when a force opposes the motion.