Three particles A, B & C start from the origin at the same time, A with a velocity 'a' along X-axis, B with a velocity 'b' along y-axis and C with velocity 'c' in XY plane along the line x = y. The magnitude of 'c' so that the three always remain collinear is:

Three particles A, B & C start from the origin at the same time, A wit

1.	Three particles A, B & C start from the origin at the same time, A with a velocity 'a' along X-axis, B with a velocity 'b' along y-axis and C with velocity 'c' in XY plane along the line x = y. The magnitude of 'c' so that the three always remain collinear is:
Answer» `(a+b)/(2)` `SQRT(AB)` `(ab)/(a+b)` `(SQRT2 ab)/(a+b)` ANSWER :D