Charging by induction: Testing Experiment

Aim

To apply your understanding of charge and conductors to make predictions of the outcomes of electroscope experiments.

Prior Knowledge

  • Charge
  • Conductors
  • Electroscope

Description of the Experiment

Sahana brings a positively charged rod close to the plate of the electroscope (without touching). With her other hand she touches the electrosope on the side opposite to the side where the rod is, then releases her hand, and then moves the rod away.

Use your model of charge to predict what will happen to the electroscope. Predict what charge (positive, negative or none) will be on the plate after Sahana's hand and the rod have been removed. How can you test whether your prediction is correct? After you answer the above questions, watch the video.

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Questions

  1. Use your knowledge of electric charge,conductors and electroscopes to predict what will happen to the electroscope when Sahana brings a positively charged rod to it without touching. Record your prediction, explain it.
  2. Predict what will happen if Sahana touches the top of the electroscope on the side opposite to the side where the rod is with her hand while holding the rod near by. Record your prediction and explain it.
  3. Predict what charge (positive, negative or none) will be on the plate after Sahana's hand and the rod have been removed. Record your prediction and explain it.
  4. Now watch the video and record the observations. Reconcile all of the discrepancies with your preditions.