( ༄|ནྲ 》 57 57 ↑ ED Tt > Solve the following problem: 1a. The half-life of 131| is 8 days. If 130 mCi of 131| was present at 9am on January 8, then how much will remain on January 24? 1b. What percentage of it (1311) will remain on February 25? J

(a) Find the total energy released in MeV in each carbon cycle (elaborated in the above problem) including the annihilation energy. (b) How does this compare with the protonproton cycle output?

Data from the appendices and the periodic table may be needed for these problems. A 60Co source is labeled 4.00 mCi, but its present activity is found to be 1.85107Bq. (a) What is the present activity in mCi? (b) How long ago did it actually have a 4.00—mCi activity?

Data from the appendices and the periodic table may be needed for these problems. Show that the activity of the 14C in 1.00 g of 12C found in living tissue is 0.250 Bq.

A beam of 168MeV nitrogen nuclei is used for cancer therapy. If this beam is directed onto a 0.200kg tumor and gives it a 2.00Sv dose, how many nitrogen nuclei were stopped? (Use an RBE of 20 for heavy ions.)

To obtain the most precise value of BE from the equation BE=[ZM(1H)+Nmn]c2m(AX)c2, we should take into account the binding energy of the electrons in the neutral atoms. Will doing this produce a larger or smaller value for BE? Why is this effect usually negligible?

(a) Calculate the radius of 58Ni, one of the most tightly bound stable nuclei. (b) What is the ratio of the radius of 58Ni to that at 258Ha, one of the largest nuclei ever made? Note that the radius of the largest nucleus is still much smaller than ?le size of an atom.

(a) Background radiation due to 226Ra averages only 0.01 mSv/y, but it can range upward depending on where a 226Ra in the 80.0kg body of a man who receives a dose of 2.50mSv/y from it, noting that each 226Ra decay emits a 4.80MeV particle. You may person lives. Find the mass of neglect dose due to daughters and assume a constant amount, evenly distributed due to balanced ingestion and handily elimination. (b) Is it surprising that such a small mass could cause a measurable radiation dose? Explain.

Data from the appendices and the periodic table may be needed for these problems. (a) Calculate the activity R in curies at 1.00 g of 226Ra. (b) Discuss why your answer is not exactly 1.00 Ci, given that the curie was originally supposed to be exactly the activity of a gram of radium.

(a) Calculate the energy released in the neutroninduced fission reaction n+235U92Kr+142Ba+2n, given m(92Kr)=91.926269 and m(142Ba)=141.916361u. (b) Confirm that the total number at nucleons and total charge are conserved in this reaction.