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Question 1: What would be the resultant charge on a sphere when a negative rod is brought near the sphere, which is then earthed on the far side?

Question 2: What is the resultant charge on an electroscope, when it is touched by a finger while a negative rod is near its top plate.

Question 3: What is the net charge inside a charged metallic ball?

Question 4: What is the force between two charges, 2 µC and 8 µC, separated by 4.0cm?

Question 5: What is the rationale for choosing the value of the unit coulomb so that an electron has a charge of $1.6 × 10^{-19} C$?

Question 6: Two identical spheres are charged, one to 6 µC, and the other to -7 µC. The spheres are allowed to touch, and then are separated. What will be the charge on the two spheres afterwards?

Question 7: Electric charge is .......... in an isolated system.

Question 8: A positively charged rod is brought close to a neutral metallic sphere. The demonstrator touches the other side of the sphere briefly, then removes the rod. What is the net charge on the sphere?

Question 9:

A demonstrator charges a rod negatively and brings it close to the top plate of an electroscope. The foil rises. He now touches the top plate with his finger and the foil falls down. He removes his finger and then takes away the rod. What happens?

Question 10: If the outside of a hollow metallic conductor is connected to an electroscope, which indicates the outside is positive, what is the net charge inside the container?

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