Question

two students are experimenting with two neutral objects – a foam square and a sample of animal fur. they rub the two together and the foam square becomes charged negatively and the fur becomes charged positively. complete the analysis of this situation.

before

#p⁺ = #e⁻
#p⁺ > #e⁻
#p⁺ < #e⁻

#p⁺ = #e⁻
#p⁺ > #e⁻
#p⁺ < #e⁻

after

#p⁺ = #e⁻
#p⁺ > #e⁻
#p⁺ < #e⁻

#p⁺ = #e⁻
#p⁺ > #e⁻
#p⁺ < #e⁻

how did the foam square become charged?

Explanation:

Step1: Analyze the charge of neutral objects

Before rubbing, both the foam square and the animal fur are neutral. For a neutral object, the number of protons (\(\#p^{+}\)) is equal to the number of electrons (\(\#e^{-}\)), so \(\#p^{+}=\#e^{-}\) for both objects before rubbing.

Step2: Analyze the charge after rubbing

When they are rubbed together, electrons are transferred. The foam square becomes negatively charged. A negative charge means that the number of electrons is greater than the number of protons, so \(\#p^{+}<\#e^{-}\) for the foam square after rubbing. The fur becomes positively charged. A positive charge means that the number of protons is greater than the number of electrons, so \(\#p^{+}>\#e^{-}\) for the fur after rubbing.

Answer:

Before: For foam square \(\#p^{+}=\#e^{-}\), for fur \(\#p^{+}=\#e^{-}\). After: For foam square \(\#p^{+}<\#e^{-}\), for fur \(\#p^{+}>\#e^{-}\)