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The work done on a particle of mass m by a force, K [x / (x² + y²)^(3/2) î + y / (x² + y²)^(3/2) ĵ] (K being a constant of appropriate dimensions), when the particle is taken from the point (a, 0) to the point (0, a) along a circular path of radius a about the origin in the x-y plane is

1. 2Kπ / a
2. Kπ / a
3. Kπ / 2a
4. 0

Correct answer: 0

Solution

The force is conservative, and the work done along a closed path (like a circular path) is zero for conservative forces. Hence, the work done is 0.

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