Modern Physics 5 Question 20
22. Results of calculations for four different designs of a fusion reactor using D-D reaction are given below. Which of these is most promising based on Lawson criterion ?
(2009)
(a) Deuteron density $=2.0 \times 10^{12} cm^{-3}$, confinement time
$$ =5.0 \times 10^{-3} s $$
(b) Deuteron density $=8.0 \times 10^{14} cm^{-3}$, confinement time $=9.0 \times 10^{-1} s$
(c) Deuteron density $=4.0 \times 10^{23} cm^{-3}$, confinement time
$$ =1.0 \times 10^{-11} s $$
(d) Deuteron density $=1.0 \times 10^{24} cm^{-3}$, confinement time
$$ =4.0 \times 10^{-12} s $$
Match the Column
| Column I | Column II | ||
|---|---|---|---|
| (A) | Nuclear fusion | (p) | Converts some matter into energy |
| (B) | Nuclear fission | (q) | Generally possible for nuclei with low atomic number |
| (C) | $\beta$-decay | (r) | Generally possible for nuclei with higher atomic number |
| (D) | Exothermic nuclear reaction |
(s) | Generally possible for weak nuclear forces |
Show Answer
Answer:
Correct Answer: 22. (c, d)
Solution:
- As given in the paragraph, a reactor is termed successful, if
$$ n t _0>5 \times 10^{14} s cm^{-3} $$
