87. On the motionless body mass m = 0,5 kg starts a force that varies according to the law F = Aі Vtj + + Ck, where k = 2 H, B = 3 N / C, C = 0.5 H, where I, j, k - the unit vectors of the coordinate axes x, y and z. Define: speed υ of the body; Module velocity υ at time t = 2 seconds after the start of motion.

Detailed solution. Decorated in Microsoft Word 2003. (Target decided to use formula editor)