E.4 Fission Quiz

1. In $^{1}_{0}\mathrm{n} + ^{235}_{92}\mathrm{U} \rightarrow\ ^{141}_{56}\mathrm{Ba} + ^{92}_{36}\mathrm{Kr} + x\,^{1}_{0}\mathrm{n}$, the value of x is:

• A. 1
• B. 2
• C. 3
• D. 4

2. Which component slows down neutrons in a reactor?

• A. Control rods
• B. Moderator
• C. Heat exchanger
• D. Shielding

3. A reactor's control rods are raised out of the core. The fission rate:

• A. Increases
• B. Decreases
• C. Stays the same
• D. Drops to zero

4. A fission reaction has a mass decrease of 0.20 u. The energy released is about:

• A. 19 MeV
• B. 190 MeV
• C. 1900 MeV
• D. 0.20 MeV

5. Spent fuel is stored in water pools at first mainly because:

• A. Water makes the waste non-radioactive
• B. The waste is still producing heat and water provides cooling and shielding
• C. Water speeds up radioactive decay
• D. Water slows neutrons for further fission