Multiple Choice Question

Question

A student is designing an investigation of the distribution of charges in conductors. She will use two conducting spheres mounted on insulating stands in the investigation. The conducting spheres are shown.

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The student wants to separate the charges of the spheres as shown.

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What should the student do in her investigation to produce these results?

A.
She should place a negatively charged rod near the left sphere.

B.
She should place a positively charged rod near the left sphere.

C.
She should place two negatively charged rods near each sphere.

D.
She should place two positively charged rods near each sphere.

Answer 1

To achieve the goal of separating the charges on the two conducting spheres, the student should induce charge separation by using a charged rod.

Given the desired configuration, where one sphere becomes negatively charged and the other positively charged, the appropriate action is to use a positively charged rod. When a positively charged rod is brought near the left sphere, it will attract electrons from that sphere towards the rod, leaving the left sphere with a net positive charge and inducing a negative charge on the right sphere by repulsion.

Therefore, the correct answer is:

B. She should place a positively charged rod near the left sphere.