Nickel can be machined with 100% current efficiency, when current density value is April 4, 2021 by admin Question: Nickel can be machined with 100% current efficiency, when current density value is A. 10 a/cm2 B. 25 a/cm2 C. 45 a/cm2 D. 80 a/cm2 Answer» b. 25 a/cm2 Note: The above multiple-choice question is for all general and Competitive Exams in India.