A force Vector F = - K(yi + xj), where k is a positive constant, acts

1.	A force Vector F = - K(yi + xj), where k is a positive constant, acts on a particle moving in the xy plane. Starting from the origin, the particle is taken along the positive x-axis to the point (a, 0), and then parallel to the y-axis to the point (a, a). The total work done by the force on the particle is(a) -2ka2 (b) 2ka2 (c) -ka2 (d) ka2
Answer» Correct answer is: (c) -ka² For the first displacement, y = 0. Hence F_x = 0 and no work is done. For the second displacement, F_y = - ka and Δy = a. Work = F_y Δ_y = - ka² .

A force Vector F = - K(yi + xj), where k is a positive constant, acts on a particle moving in the xy plane. Starting from the origin, the particle is taken along the positive x-axis to the point (a, 0), and then parallel to the y-axis to the point (a, a). The total work done by the force on the particle is(a) -2ka2 (b) 2ka2 (c) -ka2 (d) ka2

Answer»

Correct answer is: (c) -ka²

For the first displacement, y = 0. Hence F_x = 0 and no work is done. For the second displacement, F_y = - ka and Δy = a.

Work = F_y Δ_y = - ka² .

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