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hhjjy

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- Homework Statement
- In her hand a softball pitcher swings a ball of mass 0.250 kg around a vertical circular path of radius 60.0 cm before releasing it from her hand. The pitcher maintains a component of force on the ball of constant magnitude 30.0 N in the direction of motion around the complete path. The speed of the ball at the top of the circle is 15.0 m/s. If she releases the ball at the bottom of the circle, what is its speed upon release?

- Relevant Equations
- $$ \sum {W_{other forces}} = W = \Delta K + \Delta U + \Delta E_{int} $$

$$ E_{mech} = \Delta K + \Delta U $$

This is my solution ,and I just use the definition .But I still feel unclear about the concept of non-conservative force.$$ W = F x = 30N (\frac{1}{2}\pi r ) = 56.2 J $$

$$ E_{system} = \Delta K + \Delta U = W $$

$$ (K_{f}- K(i))+(U(f)-U(i)) = W $$

$$ (\frac{1}{2} *m{V_{f}}^2 -\frac{1}{2}*m{V_{i}}^2)+(mgh_{f}-mgh{i}) = W) $$

$$ V_{f} = \sqrt{V_{i}^2 + 2gh_{i} + \frac{2W}{m}} $$

I want to ask

1. Whether my solution is wrong.

2. What does the meaning of works done on a non-uniform circular motion?

$$ E_{system} = \Delta K + \Delta U = W $$

$$ (K_{f}- K(i))+(U(f)-U(i)) = W $$

$$ (\frac{1}{2} *m{V_{f}}^2 -\frac{1}{2}*m{V_{i}}^2)+(mgh_{f}-mgh{i}) = W) $$

$$ V_{f} = \sqrt{V_{i}^2 + 2gh_{i} + \frac{2W}{m}} $$

I want to ask

1. Whether my solution is wrong.

2. What does the meaning of works done on a non-uniform circular motion?

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