Understanding Centripetal Force in a Pendulum System

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In a pendulum system, the forces acting on the bob are tension and gravity, with centripetal force being the net radial force resulting from these two. The tension in the cable counteracts gravity, and the net force provides the necessary centripetal acceleration for the bob's circular motion. It's important to understand that centripetal force is not an additional force but rather a description of the net force acting towards the center of the circular path. The confusion often arises from misinterpreting centripetal force as a separate entity. Clarifying this concept helps in understanding the dynamics of pendulum motion.
Fisicks
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"A 0.400-kg pendulum bob passes through the lowest part of its path at a speed of 3.00 m/s.
What is the tension in the pendulum cable at this point of the pendulum is .8 meters long?"

I would like to ask for some help on understanding centripetal force in this particular situation. I realize gravity is pulling down on the bob, while tension is counteracting gravity, and centripetal force is also counteracting gravity.

I would like someone to explain to me why the sum of the forces here is the total centripetal force, or Tension minus force of gravity.
 
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Fisicks said:
I realize gravity is pulling down on the bob, while tension is counteracting gravity, and centripetal force is also counteracting gravity.
It sounds like you are thinking of centripetal force as if it were a third force on the bob. It's not. The only forces acting on the bob are tension and gravity. "Centripetal force" is just a name for the radial component of the net force.
 
thank you very much, that's why i was so confused. Centripetal force is just another name for net force, but in angular motion!
 
Fisicks said:
thank you very much, that's why i was so confused. Centripetal force is just another name for net force, but in angular motion!
For the radial component, yes. You could have a tangential component of force too, but it's not centripetal.
 

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