“2019年USAAAO决赛第1题”的版本间的差异
来自astro-init
Jingsong Guo（讨论 | 贡献） （创建页面，内容为“==英文题目==”） |
Jingsong Guo（讨论 | 贡献） |
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==英文题目== | ==英文题目== | ||
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| + | 1. (7 points) Assuming that the present density of baryonic matter is ρb0 = 4.17*10^28 kg/m3 , what was the density of baryonic matter at the time of Big Bang nucelosynthesis (when T = 10^10 K)? Assume the present temperature, T0 to be 2.7 K. | ||
2020年3月7日 (六) 17:15的版本
英文题目
1. (7 points) Assuming that the present density of baryonic matter is ρb0 = 4.17*10^28 kg/m3 , what was the density of baryonic matter at the time of Big Bang nucelosynthesis (when T = 10^10 K)? Assume the present temperature, T0 to be 2.7 K.
