Chapter 5, Problem 15P

|| A. man pushes on a piano of mass 180 kg 50 that it sides at a constant velocity of 12.0 cm/s down a ramp that is inclined at 11.0° above the horizontal. No appreciable friction is acting on the piano. Calculate the magnitude and direction of this push (a) if the man pushes parallel to the incline. (b) if the man pushes the piano up the plane 1nstead. also at 12.0 cm/s parallel to the inc1ine. and (c) if the man pushes horizontally. but; still with a speed or 12.0 cm/s.