During the lunar mission of Apollo 11, Armstrong and Aldrin descended to the moon’s surface in the lunar module while Collins remained in orbit in the command module. If the command module’s period was 2 hours and 20 minutes, how high above the moon’s surface did it orbit? (mmoon = 7.35 x 1022 kg, Rmoon = 1.74 x 106 m, and G = 6.67 x 10-11 N m2/kg2)

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.