Question

For sky wave propagation of $10MHz$ signal, what should be the minimum electron density in ionosphere?

• A. $\sim 1.2\times {10}^{12}{m}^{-3}$
• B. $\sim {10}^6{m}^{-3}$
• C. $\sim {10}^{14}{m}^{-3}$
• D. $\sim {10}^{22}{m}^{-3}$

Answer 1

The correct option is A $\sim 1.2\times {10}^{12}{m}^{-3}$

Using equation, ${\stackrel{-}{v}}_c=9{\mu }_{min}^{1/2}$

$\Rightarrow 10\times {10}^6=9{\mu }_{min}^{1/2}$
$\Rightarrow \mu =\frac{{10}^{14}}{81}\approx 1.2\times {10}^{12}$ units