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I need some alternative view to grasp this concept better:
I am tired and I think my brain is starting to f**k things up for me,
can someone provide a clarification/critique of this simple concept for me?
forces acting on a simple pendulum
during the cycle of the pendulum you have one force, that of mg (always pointing straight down), that can be resolved in two components.
Component of mg perpendicular to arc is Tension= (mg cos theta) and the other componet -tangent to arc- is restoring force (mg sin theta). At theta 90 (extreme position) I resolve my two forces as mg (tangential-pointing straight down) and tension T=0.
During the travel down to the equilibrium position, the restoring force vector (F=mg sin theta) gets smaller until theta=0, thus Fx=0. No net force is present in the tangential component at equilibrium, but mg cos theta is maxed out, thus greatest tension at equilibrium.
What's up with acceleration? I know that at equilibrium acceleration,is also pointing to center (radial) along the pendulum's rod. So you can say acceleration on x is 0 but acceleration in y component is not.
Is it correct to think that acceleration can be calculated from a=v^2/R (borrowed from UCM)
It follows that:
mg cos theta = mv^2/r
velocity can be obtained from conservation of energy KE=PE
WTF...I may need some sleep i think i've gotten all this wrong...
I am tired and I think my brain is starting to f**k things up for me,
can someone provide a clarification/critique of this simple concept for me?
forces acting on a simple pendulum
during the cycle of the pendulum you have one force, that of mg (always pointing straight down), that can be resolved in two components.
Component of mg perpendicular to arc is Tension= (mg cos theta) and the other componet -tangent to arc- is restoring force (mg sin theta). At theta 90 (extreme position) I resolve my two forces as mg (tangential-pointing straight down) and tension T=0.
During the travel down to the equilibrium position, the restoring force vector (F=mg sin theta) gets smaller until theta=0, thus Fx=0. No net force is present in the tangential component at equilibrium, but mg cos theta is maxed out, thus greatest tension at equilibrium.
What's up with acceleration? I know that at equilibrium acceleration,is also pointing to center (radial) along the pendulum's rod. So you can say acceleration on x is 0 but acceleration in y component is not.
Is it correct to think that acceleration can be calculated from a=v^2/R (borrowed from UCM)
It follows that:
mg cos theta = mv^2/r
velocity can be obtained from conservation of energy KE=PE
WTF...I may need some sleep i think i've gotten all this wrong...