A positively charged insulating rod is brought close to an object that is suspended by a string. If the object is attracted toward the rod we can conclude:

a. the object is positively charged

b. the object is negatively charged

c. the object is an insulator

d. the object is a conductor

e. none of the above

Answer: Option (b) is the correct answer.

Explanation:

It is known that opposite charges tend to attract each other whereas like charges tend to repel each other.

For example, when a positively charged insulating rod is brought close to an object and the object gets attracted towards the rod then it means that a negative charge is present on the object.

This is because both the object and rod gets attracted towards each other and only opposite charges tends to attract each other.

Thus, we can conclude that if the given object is attracted toward the rod we can conclude that the object is negatively charged.

b. the object is negatively charged

Explanation:

When a positively charged insulating rod is brought close to an object which gets attracted towards it, then it certainly means that the object is negatively charged because we know from the basics of electrostatics that unlike charges attract each other.

We cannot know the conductivity of the object just by being in proximity of it.