4) A block (block 5) of mass ms = 2.3 kg hangs from the end of a (massless) string which runs over a (massless frictionless) pulley. The other end of the string is connected to another block (block 4) of mass ma 6.1 kg on a surface inclined at an angle of 0-27 above the horizontal. The situation is shown below. M4 Ms a) Assuming there is no friction between block 4 and the inclined plane, find the acceleration (magnitude and direction!) of the acceleration of block 5. (0.55 m/s up!) b) Assuming there is no friction between block 4 and the inclined plane, find the tension in the string. (24 N) c) Now assume there is friction between block 4 and the plane with a coefficient of kinetic friction = 0.20. Assuming that block 4 is sliding down the plane (that is the direction of velocity) find the acceleration of block 5. (0.72 m/s down!) d) Under the same assumptions as in part c, find the tension in the string. (21 N)