Apositive rod is placed to the left of sphere a, and the spheres are separated. which best describes the spheres? sphere a is negative and sphere b is positive because protons from sphere a are attracted to the rod and move to sphere b. sphere a is negative and sphere b is positive because electrons from sphere b are attracted to the rod and move to sphere a. sphere a is positive and sphere b is negative because electrons from the rod move to sphere b and protons then move to sphere a. sphere a is positive and sphere b is negative because protons move from sphere b to the rod and also to sphere a.

When a positively charged rod is placed near the sphere A then due to the attraction force of rod all the electrons will come to the nearest surface of  sphere A and due to deficiency of electrons on the far side of sphere B it will get positive charge

This phenomenon of charge separation is know as induction of charge

So sphere A will get negative charge and sphere B will get positive charge on its surface after they got separated

So here correct answer would be

Sphere A is negative and sphere B is positive because electrons from sphere B are attracted to the rod and move to sphere A.

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