

MCQOPTIONS
Saved Bookmarks
This section includes 11 Mcqs, each offering curated multiple-choice questions to sharpen your Antennas knowledge and support exam preparation. Choose a topic below to get started.
1. |
Find the MUF for the wave operating at a critical frequency 6MHz and having the skip distance d as 25km and virtual height of 100km in the ionosphere layer. |
A. | 6.05MHz |
B. | 1.25MHz |
C. | 1.025MHz |
D. | 3.25MHz |
Answer» B. 1.25MHz | |
2. |
What is the refractive index of the region operating at 16MHz frequency with the electron density 49 1010/cm3? |
A. | 0.518 |
B. | 0.919 |
C. | 0.155 |
D. | 0.845 |
Answer» C. 0.155 | |
3. |
Suppose a ray is incident normally in the ionosphere region with electron density 25 1010/cm3, then the Maximum usable frequency is _____ |
A. | 5GHz |
B. | 45MHz |
C. | 4.5MHz |
D. | 125GHz |
Answer» D. 125GHz | |
4. |
Which of the following is true when a ray is incident normally in an Ionosphere region? |
A. | MUF is equal to critical frequency |
B. | MUF is greater than critical frequency |
C. | MUF is less than critical frequency |
D. | MUF is zero |
Answer» B. MUF is greater than critical frequency | |
5. |
What is the value of maximum usable frequency when the incident angle is 60 and the critical frequency is 4.5MHz? |
A. | 4.5MHz |
B. | 2.25MHz |
C. | 9MHz |
D. | 18MHz |
Answer» D. 18MHz | |
6. |
Skip distance is the _____ |
A. | Minimum distance at which wave returns back at the lowest possible frequency |
B. | Maximum distance at which wave returns back at the critical frequency |
C. | Minimum distance at which wave returns back at the critical angle |
D. | Maximum distance at which wave returns back at the lowest possible frequency |
Answer» D. Maximum distance at which wave returns back at the lowest possible frequency | |
7. |
Relation between MUF and critical frequency is ______ |
A. | f<sub>c</sub> = f<sub>MUF</sub> sec <sub>i</sub> |
B. | f<sub>MUF</sub> = f<sub>c</sub> sec<sup>2</sup> <sub>i</sub> |
C. | f<sub>c</sub> = f<sub>MUF</sub> sin <sub>i</sub> |
D. | f<sub>MUF</sub> = f<sub>c</sub> sec <sub>i</sub> |
Answer» E. | |
8. |
Suppose a ray is incident normally in the ionosphere region with electron density 36 1010/cm3, then the critical frequency is _____ |
A. | 5GHz |
B. | 54MHz |
C. | 5.4MHz |
D. | 324GHz |
Answer» D. 324GHz | |
9. |
The frequency below which the entire power gets absorbed is called as ____ |
A. | MUF |
B. | LUF |
C. | Critical frequency |
D. | Optimum frequency |
Answer» C. Critical frequency | |
10. |
If wave exceeds the MUF then it is not reflected back. |
A. | True |
B. | False |
Answer» B. False | |
11. |
The maximum possible frequency for which the wave is reflected back for a given distance of propagation in the ionosphere layer is called as_______ |
A. | Maximum usable frequency |
B. | Critical frequency |
C. | Resonance frequency |
D. | Dominating frequency |
Answer» B. Critical frequency | |