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Table of Contents
Forces
A force is an interaction that would change the motion of a given object. The diagram below shows the forces typical of an object in any given system.
Where:
- $F_n$ is the normal force
- $F_r$ is friction
- $F_a$ is the applied force
- and $W$ being weight
Weight
Mass is the density of the object while weight is its resistance against gravity. Volume is related to mass via density. Weight is mass multiplied by gravity. $W = mg$
Applied Force
Applied force is the force exerted on an object in a system externally. Typically it's given to you. It can also be substituted with a force like tension.
Normal Force
The normal force is what is exerted when a object rests against another. Typically, this force is equivalent to the weight of the object1), unless it is a special situation like an incline plane. In those cases, the normal force may be offset from the weight.
Friction
Friction is a force caused by the collision of surfaces that are inherently uneven. It is mathematically defined as $F_r = \mu F_n$ where $F_r$ is friction, $F_n$ is the normal force2), and $\mu$ being the coefficient of friction3).
Tension
Check the last few sentences to see if they're valid
Tension is a force that a rope4) exerts pulling one object to another. The acceleration of tension can be calculated by summing the forces of each object under tension by the sum of their masses5). From there, you can use Newton's Second Law 6) to calculate the force of tension, with $F_{net}$ being the sum of all forces in the system ($\sum F$), $m$ being the mass of the two objects in tension, and $a$ being the value calculated before.