A) \[\tilde{\ }1.2\times {{10}^{12}}{{m}^{-3}}\]
B) \[\tilde{\ }{{10}^{6}}\,{{m}^{-3}}\]
C) \[\tilde{\ }{{10}^{14}}\,{{m}^{-3}}\]
D) \[\tilde{\ }{{10}^{22}}\,{{m}^{-3}}\]
Correct Answer: A
Solution :
The critical frequency of sky wave undergoing reflection from a layer of atmosphere is \[{{f}_{c}}=\sqrt[9]{{{N}_{\max }}}\] where N is electron density per \[{{m}^{3}}.\] \[\therefore \] \[{{N}_{\max }}=\frac{{{f}_{c}}^{2}}{81}=\frac{{{(10\times {{10}^{6}})}^{2}}}{81}\] \[=1.2\times {{10}^{12}}\,{{m}^{-3}}\]You need to login to perform this action.
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