The half-life of a radioactive element is 5. Calculate its decay constant? by Sunday | Aug 27 | Physics WAEC | 0 comments A. 0.113s‾¹ B. 0.436 s‾¹ C. 0.139 s‾¹ D. 0.193 s‾¹ Correct Answer: Option C – 0.139 s‾¹ Users Also Read These:A radioactive substance has a half-life of 20 hours.…The half-life of a radioactive substance is 15…A radioactive element has a decay constant of…The number of protons in an element increased by one…In 24 days a radioactive isotope decreases in mass…