- Radioisotopes Are Used In A Variety Of Manufacturing And Testing Techniques Wear Measurements Can Be Made Using The Fol 1 (173.97 KiB) Viewed 58 times
Radioisotopes are used in a variety of manufacturing and testing techniques. Wear measurements can be made using the following method. An automobile engine is produced using piston rings with a total mass of 100 g with a radioactivity rate of 9.4 mCi g from the isotope 5°Fe whose half-life is 44.5 days. The engine is test-run for 1500 hours, after which the oil is drained, and its activity is measured. If the activity of the engine oil is 3.72 x 10€ decays/s. For parts (a) through (), you will only need to consider activity rates, half-lives and relative quantities of materials. (a) How much mass was worn from the piston rings per hour of operation? (b) What would be the activity in the piston after 0.0802 grams has been worn off the piston? (C) If the number of atoms of 59 Fe in the oil is found to be 1.22 x 10' after the piston had been used for a total time of 6.00 years, then how many moles of 59Fe were in the piston to begin with? For parts (d) through (f) you will need to consider conservation of energy and/or momentum in addition to half-life calculations. Use relativistic energy and momentum. (d) Iron-59 has an atomic mass of 58.9348755 u and decays into Cobolt-59 through 100% B-decay (emission of an electron from the nucleus which transforms a neutron into a proton). Cobolt-59 has an atomic mass of 58.9331950 u. Based off your answers above, how much total energy is emitted through the decay of 5Fe during the first year if the piston's operation? (e) What percentage of the total energy released during the decay of a single 5°Fe atom at rest is imparted to the electron? (f) If we consider an individual 59Fe atom at rest, what will be the final de Broglie wavelengths of the electron and the 59Co created through the decay?