Aperson pushes a box up a ramp that is 3m long and 1m high. if the box has a mass of 20 kg and the person pushes with a force of 80 n, what is the efficency of the ramp?

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.