Pendulum SHM: Vector Direction of Weight vs. Tension

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The discussion centers on the vector direction of forces acting on a pendulum, specifically the weight and tension. The net restoring force is identified as Fnet = mg sin θ, emphasizing that this force is derived from the weight rather than tension. The tension force must be resolved into components, with only the tangential component contributing to the net force acting on the pendulum's bob. Illustrations are suggested to clarify the forces and their components in both tangential and radial directions. Understanding these vector relationships is crucial for analyzing pendulum motion.
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I've seen in many sites that a pendulum restoring force Fnet = mg sin theta... Why did we actually get the vector direction of the weight and not the vector of the tension.. Simply, as in centrepetal force.. It would be Tsin theta would be the net restoring force? Thanks!
 
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The restoring force is the net force acting on the pendulum's bob.
If you add the tension and the weight (as vectors) and consider inextensible suspension string the resultant is tangent to the trajectory and its magnitude is mg sinθ.
 
Can i have illustrations then??
 
Sure you can. Draw the forces acting on the pendulum and then take the components along the tangential and radial directions.
 

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