A furniture crate of mass 60 kg is at rest a loading ramp that makes an angle of 25° with the horizontal The coefficient of kinetic friction between the crate and the ramp is 0.2. What force, applied parallel to the incline, is required to push the crate up the incline at a constant speed?

Asolid round steel rod 6.25 mm in diameter and 375 mm long is rigidly bonded to the end of solid square brass rod 25 mm on a side and 300 mm long. the geometric axes of the bare are along the same line. an axial tensile force of 5.4 kn is applied at the extreme ends of the assembly. for steel e = 200 gpa and for brass e = 90 gpa. determine the total elongation for the assembly.