MCQOPTIONS
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MCQOPTIONS
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. | fc = fMUF secθi |
| B. | fMUF = fc sec2 θi |
| C. | fc = fMUF sinθi |
| D. | fMUF = fc secθi |
| 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 | |