NCERT Exercise 1.2 - Electric Charges and Fields
Question: The electrostatic force on a small sphere of charge 0.4 μC due to another small sphere of charge –0.8 μC in air is 0.2 N. (a) What is the distance between the two spheres? (b) What is the force on the second sphere due to the first?
Answer: (a) The distance between the two spheres is **0.12 m (12 cm)**. (b) The force on the second sphere due to the first is **0.2 N** (attractive, directed toward the first sphere — Newton's Third Law).
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