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JEE Main202125 Feb 2021Evening ShiftPhysicsElectrostaticsActual

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 a 21 × 10 - 8 C . The value of a will be ___.[Given g = 10 m s - 2 ]

Correct answer

0

Step-by-step solution

. T cos θ = m g = 10 × 10 - 6 × 10 = 10 - 4 T sin θ = 9 × 10 9 × q 2 0 . 04 = F tan θ = = 0 . 1 0 . 24 = F m g q = 2 10 3 24 × 10 - 8 0 . 95 × 10 - 8 = a 21 × 10 - 8 a = 20

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