Muscle Force Continued
To determine the muscle force needed to achieve a particular activity :
RECALL: Resultant force is equal to the sum of individual forces of a system.
In this example, the quadriceps muscles apply a force (Fmuscle) to the leg while the weight on the foot provides a resistant force (Fweight).
In order for the leg to move in the direction of Fmuscle, this force must be larger then that of Fweight.
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