Two small spheres with charges q1 = +9 nc and q2 = -3 nc are placed at marks x1 = -2 cm and x2 = 13 cm. where along the x-axis should you place a third sphere with charge q3 so that the sum of the forces exerted by the first two spheres on the third one is zero?

Explanation:

Given

Charge  on particles

Third charge must be placed right side of as will attract and so net force will be zero

Electrostatic force is given by

suppose is at a distance of x cm from

what do the notation's look like?

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