Ball on a string: Testing Experiment

Aim

Predict the path of a ball which is being swung in a vertical circle on a string and released when the string is parallel to the floor.

Prior Knowledge

• Newton's second law
• Direction of instantaneous velocity during circular motion

Description of the Experiment

Predict the path of a ball which is being swung in a vertical circle on a string and released when the string is parallel to the floor. Think of the direction of the instantaneous velocity of the ball at the moment of release.

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Questions

1. Did the result of the experiment match your prediction? If no, how can you modify the reasoning that led you to the prediction to justify the result?
2. Can you predict how high the ball will go if you know the radius of the circle and the period of the ball?
3. The height of the first person is about 165 cm. Use this information to predict the height of the ball and then measure the actual height to find out whether your prediction makes sense.
4. What are possible uncertainties in your estimation?