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JEE Main202118 Mar 2021Evening ShiftPhysicsElectrostaticsActual

An infinite number of point charges, each carrying 1 μ C charge, are placed along the y-axis at y = 1 m , 2 m , 4 m , 8 m . . . . The total force on a 1 C point charge, placed at the origin, is x × 10 3 N . The value of x , to the nearest integer, is ___ . [Take 1 4 π ϵ 0 = 9 × 10 9 N m 2 C - 2 ]

Correct answer

0

Step-by-step solution

F = k 1   C 1   μ C 1 + 1 2 2 + 1 4 2 + 1 8 2 + … = 9 × 10 3 1 1 - 1 4 = 12 × 10 3   N

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