Phys320 – Spring 2004 (Baski) Quiz #6: Nuclear Physics April 21, 2004 Name: ___SOLUTIONS_____ Complete both of the following problems. Show all of your work for full credit. Problem 1: Radioactivity The counting rate from a radioactive source is initially 4 million decays per second, and it decreases to 500,000 s–1after 6 seconds. Find the τand half-life of this source in seconds. Also, find the counting rate after 20 seconds has elapsed. Solving for τin the decay equation R = Roe– t/τgives: ( 29( 291/2656116s2.885 sandln2(2.885)(0.693)2.0s410lnln510exp(410)exp20s2.885s3,903soottttRRRRtst--======
This is the end of the preview. Sign up
access the rest of the document.