- #1

songoku

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- Homework Statement
- The picture shows a pendulum in its upward swing, that is, the velocity vector for the pendulum is pointing in the direction of E. What is the direction of the net force acting on the pendulum?

- Relevant Equations
- Not sure

I imagine y - axis is parallel to direction of A and x - axis is parallel to direction of E. There are two forces acting on the pendulum: tension in direction of A and weight in direction of D.

I break the weight into 2 components: W sin θ in opposite direction to tension and W cos θ in direction of C (where θ is angle between D and C). Tension should be bigger than W sin θ to provide centripetal force so the resultant of force in y - axis is in the direction of A and resultant of force in x - direction is in direction of C hence the direction of net force will be B.

But the answer is C. Where is my mistake?

Thanks