Which of the following statements is $NOT$ correct?

  • A
    Ground wave signals are more stable than sky wave signals.
  • B
    The critical frequency of an ionospheric layer is the highest frequency that will be reflected back by the layer when it is incident vertically.
  • C
    Electromagnetic waves of frequencies higher than about $30 \, MHz$ cannot penetrate the ionosphere.
  • D
    Sky wave signals in the broadcast frequency range are stronger at night than in the daytime.

Explore More

Similar Questions

The total power in an $AM$ wave is $1500 \ W$. What is the power transmitted by the carrier for $100\%$ modulation (in $W$)?

Sky wave propagation is not possible for frequencies

The $...........$ is the link connecting the transmitter and the receiver.

For transmission of e.m. wave of audible frequency,these waves are superimposed with waves of

$A$ modulated signal is given by $C_m(t) = A_c \sin \omega_c t + \mu A_c \sin \omega_m t \sin \omega_c t$,where $\mu$ is the modulation index. To keep the signal without distortion,the value of $\mu$ should be

Vedclass Products

For Students

Vedclass Test Series

Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.

Start Free Trial
For Teachers

Exam Paper Generator

Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.

Try Free
For Institutes

Online Exam Module

Live online exams with unlimited students, 360° analytics & white-label branding.

See Demo