Charging by touching: Observation Experiment

Aim

To expand your model of the electroscope

Prior Knowledge

• Charge
• Conductors

Description of the Experiment

In the video we videotaped 5 experiments. Pause the video after you view each one and explain your observations. Notice that Sahana touches the electroscope only once - in the first experiment. In all other instances she brings the rods close to different parts of the electrosope but does not actually touch it. The rod with which she touches the electroscope is negatively charged, the transparent plastic rod is positively charged.

	Frame rate: 15fps Size: 480 X 320 File Size: 0.81Mb
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Questions

Pause the video after you view each experiment and answer two questions corresponding to this experiment. Make sure that you understand the difference between the "description" and the "explanation".

1. Describe what happens to the leaf of the indicator mechanism after the plate has been touched with a negatively charged rod. Explain why it happens.
2. Describe what happens to the leaf of the indicator when the negatively charged rod is brought close (without touching) to the indicator. Explain why it happens.
3. Describe what happens to the leaf of the indicator when the negatively charged rod is brought close (without touching) to the plate. Explain why it happens.
4. Describe what happens to the indicator when a positively charged rod is brought close (without touching) to the plate. Explain why it happens.
5. Describe what happens to the indicator when a positively charged rod is brought close (without touching) to leaf of the the indicator. Explain why it happens.