Anyone like to work on cars

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.

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An 800 kg car is moving at 32 m/s when it hits the afterburner. the after burner applies a 180,000 n force for 25 seconds. what is the rockets final speed?