A negatively charged insulating rod is brought close to a sphere that is suspended by an insulating string. It is observed that the rod is attracted to the sphere. Which of the following observations are possibly correct?

Question

I. The sphere is positively charged.
II. The sphere is negatively charged.
III. The sphere is an uncharged conductor.
Both I and III
III only
II only
Both II and III
I only

Answer 1

To determine which observations are possibly correct based on the given scenario, let's analyze each statement:

1. Observation I: The sphere is positively charged.

   • If the sphere is positively charged, it would indeed be attracted to the negatively charged rod. Therefore, this observation could be correct.

2. Observation II: The sphere is negatively charged.

   • If the sphere is negatively charged, it would repel the negatively charged rod. Therefore, this observation cannot be correct, since we see attraction between the rod and the sphere.

3. Observation III: The sphere is an uncharged conductor.

   • An uncharged conductor would have free electrons that can move in response to the electric field created by the positively charged rod. Consequently, it could induce a positive charge on the side of the sphere closest to the rod and a negative charge on the side farther from it, leading to an attraction. Therefore, this observation can be correct.

Given this analysis, the correct observations that could be made from the scenario are:

• I (the sphere can be positively charged) and III (the sphere can be an uncharged conductor).

Thus, the option that includes both observations I and III is correct.

Final answer: Both I and III.