<span> An electroscope that might have a static charge is tested on a metal surface. From there, the charges move to the metal and straight to the foil leaves. If they repel, or move away from each other, that means they have identical charges. This applies for both positive and negative static electricity.
work cited: School of champions, Google
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1. I think a drum would be the easiest instrument to explain. You can vary the pitch and loudness by hitting it with different intensities or at different points or angles.
PS. I'm not talking about a drumset. I'm talking about an ordinary drum.
2. Different types of instruments sound different even though they play the same notes because they use different mechanisms for producing sound.
The reading on the scale is greater than your actual weight.