The platform shown has a mass of M = 50 kg and rolls without slipping down an inclined plane. of ø = 10° on four wheels (in the figure only two of them are shown, but the other two are behind). Each of the four wheels have a radius r = 200 mm and a mass of m = 6 kg and can be treated as disks.
The platform has an initial velocity of Vo = 3 m/s down the incline as shown. A constant voltage T is applied upward through a cable of negligible mass and in a time of t = 8 s the initial velocity changes to a velocity of v = 3 m/s but directed upwards on the inclined plane.

A) Find the magnitude of the tension T applied to the platform.