本题目来源于试卷: Nuclear & Quantum Physics E.5 Stellar Properties & Processes，类别为 IB物理学
[单选题]
For fusion reactions to occur in a cloud of 7q*r(cx.-rk ev(y m))mgg znl stellar dust,z5uk2dgf1jw)tumk h-9 1 pn 0q a combination of high temperature and high density among hydrogen nucgf h)kk-9djtn umuw0q12z 51plei is essential. Which of the following correctly shows why high temperature and high pressure are needed?
A. High temperature is To get hydrogen nuclei sufficiently close ; High density is To get a high rate of collision
B. High temperature is To get a high rate of collision ; High density is To get hydrogen nuclei sufficiently close
C. High temperature is To get hydrogen nuclei sufficiently far away ; High density is To get a low rate of collision
D. High temperature is To get a low rate of collision ; High density is To get hydrogen nuclei sufficiently far away
参考答案: A
本题详细解析:
Explanation: To initiate hydrogen fusion, the protons in two hydrogen nuclei must be brought within the range of the strong nuclear force. This can be achieved by raising the temperature of the nuclei so that their kinetic energy is high enough. However, even if the nuclei are close enough, the majority of collisions will not result in fusion. Therefore, the number of collisions must be high enough to ensure that a significant number of fusion reactions occur. This can be achieved by increasing the density and pressure of the nuclei.
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