Solution of task 15.5.8 from the collection of Kepe OE

Solution of task 15.5.8 from the collection of Kepe OE

15.5.8
Plate 1 with a mass of 40 kg moves translationally and rectilinearly at a speed of v1 = 1
M / s. The body 2 with a mass of 10 kg moves with respect to the plate translationally with a velocity vr = 0,4 m / s.
Determine the kinetic energy of a system of bodies if the vectors v1 and vr are parallel.
(Answer 29.8)