Understandings:
1.C.1 Inertial mass is the property of an object or a system that determines how its motion changes when it interacts with other objects or systems.
3.A.2 Forces are described by vectors
a. Forces are detected by their influence on the motion of an object.
b. Forces have magnitude and direction.
3.A.3 A force exerted on an object is always due to the interaction of that object with another object.
a. An object cannot exert a force on itself.
b. Even though an object is at rest, there may be forces exerted on that object by other objects.
c. The acceleration of an object, but not necessarily its velocity, is always in the direction of the net force exerted on the object by other objects.
3.A.4 If one object exerts a force on a second object, the second object always exerts a force
of equal magnitude on the first object in the opposite direction.
3.B.1 If an object of interest interacts with several other objects, the net force is the vector sum of the individual forces.
3.B.2 Free-body diagrams are useful tools for visualizing forces being exerted on a single object and writing the equations that represent a physical situation.
a. An object can be drawn as if it was extracted from its environment and the interactions with the environment identified.
b. A force exerted on an object can be represented as an arrow whose length represents the magnitude of the force and whose direction shows the direction of the force.
c. A coordinate system with one axis parallel to the direction of the acceleration simplifies the translation from the free-body diagram to the algebraic representation.
3.C.4 Contact forces result from the interaction of one object touching another object and they arise from interatomic electric forces. These forces include tension, friction, normal, and spring.
4.A.3 Forces that systems exert on each other are due to interactions between objects in the systems. If the interacting objects are parts of the same system, there will be no change in the center-of-mass velocity of that system.
Content Goals:
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