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The electron density of a layer of ionos...

The electron density of a layer of ionosphere at a height 150 km from the earth's surface is 9 × 109 per m3. For the sky transmission from this layer up to a range of 250 km,
The critical frequency of the layer is

A

2 Hz

B

2.7 Hz

C

2.78 kHz

D

2.7 MHz

Text Solution

Verified by Experts

The correct Answer is:
D
`f_c = 9 sqrt(N_m) = 9 xx sqrt ( 9 xx 10^(10))`
`= 2.7 xx 10^6 Hz= 2.7 MHz `
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