Two rods of equal length (0.55 m) and diameter (1.7 cm) are placed end to end. One

Question:

Two rods of equal length (0.55 m) and diameter (1.7 cm) are placed end to end. One rod is aluminum, the other is brass. If a compressive force of 8400 N is applied to the rods,
(a) How much does their combined length decrease?
(b) Which of the rods changes its length by the greatest amount? Explain.