A high school student has the following observation about therub-the-glass-rod-w

Question

A high school student has the following observation about therub-the-glass-rod-with-the-rabbit-fur demo: "Before you started,neither the fur nor the rod were attracted to each other, so theydidn't have any charged particles to start with. After you rubbedthem together, they were attracted to each other. Opposite chargesattract, so the rubbing must have made positive charges appear on,let's say, the fur and negative charges appear on theglass."

Like most incorrect physics explanations, this one is notcompletely wrong...just imprecise. Your job in this essay is tore-write this students' explanation of the demo to be morephysically precise as to what exactly is going on in therub-the-glass-rod-with-the-rabbit-fur demo.

THIS IS MY ANSWER. IS IT CORRECT? : Before we started, the rod and fur did not attract each otherbeacause they were neutral i.e. the negative charge on fur isequal to positive charge on fur and the same ids true for theglass rod. On rubbing them together makes charge transfer possiblebetween them. Suppose negative charge is tranferred from fur toglass rod. This will make the rod negatively charged and leaves anet postive charge on fur. Since opposite charges attract, fur andlass rod will attract now.

THIS IS MY ANSWER. IS IT CORRECT? : Before we started, the rod and fur did not attract each otherbeacause they were neutral i.e. the negative charge on fur isequal to positive charge on fur and the same ids true for theglass rod. On rubbing them together makes charge transfer possiblebetween them. Suppose negative charge is tranferred from fur toglass rod. This will make the rod negatively charged and leaves anet postive charge on fur. Since opposite charges attract, fur andlass rod will attract now.

Explanation / Answer

Right.  The rubbing transfers electrons, which you have correct in your answer.  The fallacy of the observation in the question is when it talks about how it "made positive charges appear" which is impossible.

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