Question

Two small spheres each of mass 10 mg are suspended from a point by threads 0.5 m long. They are equally charged and repel each other to a distance of 0.20 m. The charge on each of the sphere is \(\frac{a}{21} \times 10^{-8} C\). 
The value of 'a' will be ______. [Given g = 10 ms–2]

Answer 1

The correct answer is a = 20

mass, m₁ = 10 mg mass, m₂ = 10 mg distance, d = 0.20 m