Refractive index of ionosphere is:

Statement 1: The refractive index of the ionosphere increases as we go from the lower to upper layers in the ionosphere. Statement 2: The degree ofionization is higher at the upper layers then at the lower layers of the ionosphere.

Statement-I : Electromagnetic waves with frequencies smaller than the critical frequency of ionosphere cannot be used for communication using sky wave propagation Statement-II : The refractive index of the ionosphere becomes very high for frequency.

Statement-I : Electromagnetic waves with frequencies smaller than the critical frequency of ionosphere cannot be used for communication using sky wave propagation Statement-II : The refractive index of the ionosphere becomes very high for frequency.

Assertion : Electromagnetic waves with frequencies more than the critical frequency of ionosphere cannot be used for communication using sky wave propagation. Reason : The refractive index of the ionosphere becomes very high for frequencies higher than the critical frequency .

Assertion : Electromagentic waves with frequencies more than the cirtical frequency of ionosphere cannot be used for communication using sky wave propagation. Reason : The refractive index of the ionosphere becomes very high for frequencies higher than the critical frequency .