Two particles are projected simultaneously in the same vertical plane, from the with speed `u_(1)` and `u_(2)` at angle of projection `theta_(1)` and `theta_(2)` respectively with the horizontal. The path followed by one, as seen by other (as long as both are in flight), is

Two particles are projected simultaneously in the same vertical plane, with speed u_(1) and u_(2) at angle of projection theta_(1) and theta_(2) respectively with the horizontal. The path followed by one, as seen by other (as long as both are in flight), is

Two particles are projected simultaneously in the same vertical plane from the same point, with different speeds u_(1) and u_(2) , making angles theta_(1) and theta_(2) respectively with the horizontal, such that u_(1) cos theta_(1) = u_(2) cos theta_(2) . The path followed by one, as seen by the other (as long as both are in flight), is

Two particles are projected simultaneously in the same vertical plane from the same point, with different speeds u_(1) and u_(2) , making angles theta_(1) and theta_(2) respectively with the horizontal, such that u_(1) cos theta_(1) = u_(2) cos theta_(2) . The path followed by one, as seen by the other (as long as both are in flight), is

Two particles are projected simultaneously with the same speed v in the same vertical plane with angles of elevation theta , and 2theta , where theta lt 45^(@) .At what time will velocities be parallel?