Which statement about copper is true?

• A. Cold rolled copper is less malleable than soft copper, but stronger.
• B. Cold rolled copper is more malleable than soft copper, but weaker.
• C. Cold rolled copper weighs more than soft copper.
• D. Cold rolled copper cannot be formed.

Answer: (A)

Cold working copper by rolling strengthens it through work hardening, while reducing its ductility. When copper is cold rolled, dislocations multiply and pile up, making slip more difficult. This raises yield and tensile strength but lowers malleability. So cold rolled copper becomes stronger and less malleable than soft (annealed) copper. The weight or mass doesn't change from this process—the density stays the same, so it doesn’t weigh more. The metal can still be formed, just with more force and sometimes after relieving the work hardening by annealing if greater ductility is needed.