question_answer 31)

A particle is moving in a circular path of radius r. The displacement after half a circle would be (a) zero                                (b) p r                                    (c) 2r                                      (c) 2 p r

Answer:

(c) Given, after half the circle, the particle will reach the diametrically opposite point i.e., from point A to point B. And we know displacement is shortest path between initial and final point. Displacement after half circle =AB=OA+OB           [ Given, OA and OB = r] Hence, the displacement after half circle is 2r.