2.3.3 The velocity of a projectile 2.0 s after its launch can be found from the vector diagram V= 19.6 m s-1 (right). What was the launch velocity of the projectile? V. = 39.2 m s-1 39.2 m s ' at 450 to the horizontal. 43.8 m s ' at 30 to the horizontal. 55.4 m s ' at 450 to the horizontal. 55.4 m s ' at 30 to the horizontal. Extension: Which two answers should be recognised as being incorrect without doing any calculations? Explain why