23 14 This question is about electrostatics. (a) Dan hangs a lightweight ball between two charged metal plates using nylon thread. The ball has a metal coating.
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high voltage The ball is moved so that it touches the positive plate. When the ball is released, it swings and touches the negative plate. It then continues to swing backwards and forwards between the plates touching each one in turn. Explain why this happens. ................................................................................................................................................... ................................................................................................................................................... ................................................................................................................................................... .............................................................................................................................................. [3]
Š OCR 2015
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