Gravitation

  • It’s the force that acts on a body, attracting it towards a second body. Usually the second body is the Earth.

Weight

  • Weight is the magnitude of net force one would need to apply to prevent a body from freely falling.
  • This is the same as the gravitational force, but in the opposite direction.

Normal Force

  • When a body is pushed against another body, each of the bodies exert some force on the other body.
  • This force is called the normal force and it is perpendicular to the surface of the exerting body.

Example:

  • When an box is kept on a table the body is pulled toward the earth with .
  • The amount of force required to hold this up would be .
  • The table holds up the body without breaking the normal force exerted by the table on the box is .