A) 5.6 km/s
B) 11.2 km/s
C) 22.4 km/s
D) 44.8 km/s
Correct Answer: C
Solution :
\[{{V}_{e}}\,\,=\,\,\frac{2G{{M}_{e}}}{{{\operatorname{R}}_{e}}}\,\,=\,\,11.2\,\,km/s\] Now \[M=2{{M}_{e}}\And R'={{R}_{e}}/2\] \[\,so\,\,\,V{{'}_{e}}\,=\frac{1G(2{{M}_{e}})}{({{R}_{e}}/2)}\,\,=\,\,2\frac{2G{{M}_{e}}}{{{\operatorname{R}}_{e}}}\,\,=\,\,2\times 11.2\,\,\] \[=\text{ }22.4\text{ }km/s\]You need to login to perform this action.
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