Force types

Normal Force

Exists whenever two surfaces are presses against one another. (Ex; sit on a chair, stand on floor) In all cases your body and another surface are being pressed together; this pressing results in a force on your body and on the object called normal force.

Gravity Force

Non contact force which is the result of an interaction between two masses. All objects with mass are attracted to each other due to gravity. When the earth or a very massive object is present, the gravity force is significant in size. For an object on earth, you can always count on this force being present.

Applied force

Applied force is the result of a person pushing or pulling on an object. Applying a force could be considered a sub type of the others.

Friction force

Friction results when two touching surfaces slide across each other (sliding friction). Or attempting to slide across each other (static friction). Read problem carefully to determine if the object is moving across, if it is, then its sliding friction. To determine if the object is stationary on an inclined surface (inclined, like mountain, stationary = stopped), if it is, then theres static friction holding it in place.

Tension force

Tension is the force that happens when a rope, string, cable, or wire is attached to an object and exerting a push/pull to the the object.

Air resistance Force

Air Resistance results when there is relative motion between the object and the surrounding air (Ex: a kite being pulled through the air, a bird flying). This force is caused by the collisions between air particles and the moving object. Wherever an object is moving (+ there is air present around it), their will be an air resistance force.