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Forces

  • Force – a push or a pull
  • Net force – total of all forces on an object
  • Balanced forces – balanced forces means that the net force = zero
  • Unbalanced forces – unbalanced forces on an object cause the object to move in the direction of the larger force or the net force. Unbalanced forces cause the acceleration of the object.
  • Friction – force that brings objects to a stop.
  • Static Friction-two surfaces in contact are prevented from sliding past one another – must overcome this force to begin moving a stationary object.
  • Sliding Friction-brings a sliding object to a stop due to contact of two surfaces.
  • Rolling Friction-force between surface of wheel and surface that the object is rolling on.
  • Air Resistance – A frictional force between air molecules and a falling object – the larger the surface area of the falling object, the larger the force of the air resistance.
  • Fluid friction – force between an object and a liquid.
  • First Law of Motion – an object at rest will stay at rest and an object in motion will stay in motion unless an outside force acts upon it.
  • Second Law of Motion – acceleration of an object is in the same direction as the net force.
  • Third Law of Motion – for every action force, there is an equal and opposite reaction force.

Forces

Lecture Slides are screen-captured images of important points in the lecture. Students can download and print out these lecture slide images to do practice problems as well as take notes while watching the lecture.

Chemistry: Physical Science