Forces
Explore different forces we experience in our daily lives. Represent the forces acting on an object using a free-body diagram. Learn how to use the individual forces acting on an object to determine the net force acting on the object.
▶ Intro to forces (part 1)
A force is a push or pull. There are several types, including: applied (from person or machine), tension (from string or cable), gravity (between masses), normal (perpendicular to surface), friction (moving across a surface), thrust (from pushing something the other way), drag (resistance from air or other fluid), buoyancy (from displacing a fluid), and lift (on wings moving through air).
▶ Intro to forces (part 2)
A free body diagram (FBD) models the forces acting on an object. The object is replaced by a square. The individual force vectors are shown as arrows, and magnitudes usually measured in newtons. To determine the net force in the horizontal (x) or vertical (y) direction, add forces pointing in the same direction, and subtract forces in the opposite direction.
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